Add launcher coordinator IPC and startup reservation

Introduce a launcher coordinator to reserve startup ownership and prevent duplicate host launches. Adds a NamedPipe-based IPC server/client (LauncherCoordinatorIpcServer/Client), coordinator messages/models, and PublicShellStatus/activation types for richer shell reporting. Enhances StartupAttemptRecord and StartupAttemptRegistry to track coordinator pid/pipe, heartbeat, reserved-before-host-start, and public IPC status, plus new reservation/heartbeat APIs and takeover logic. Wire coordinator into App and LauncherFlowCoordinator to attach secondary launchers, publish coordinator status, probe existing hosts, and include more detailed launch result details. Also adds unit tests and docs describing coordinator and startup visuals behavior.

.trae/specs/launcher-shell-hardening/launcher-coordinator-addendum.md

@@ -0,0 +1,29 @@
+# Launcher Coordinator And Always-On Tray Addendum
+
+## Launcher-to-launcher coordination
+
+- Launcher reserves startup ownership in `%LocalAppData%\LanMountainDesktop\.launcher\state\startup-attempt.json` before it starts the host process.
+- The reserved record includes `CoordinatorPid`, `CoordinatorPipeName`, `HeartbeatAtUtc`, `PublicIpcConnected`, `ShellStatus`, and `ReservedBeforeHostStart`.
+- Only the active coordinator may call `Process.Start()` for the host. Secondary Launchers attach to the coordinator pipe and request desktop activation or status.
+- If the coordinator heartbeat is newer than `10s` and the coordinator pid is alive, a new Launcher must not take over.
+- If the coordinator is stale, the next Launcher may take over the same pending attempt instead of creating a second host attempt.
+- Normal launches probe Host Public IPC first. If a host is already running, Launcher activates that instance and exits without starting another host.
+
+## Finer shell status
+
+- Public shell IPC exposes `GetShellStatusAsync()`, `ActivateMainWindowWithStatusAsync()`, `EnsureTrayReadyAsync()`, and `EnsureTaskbarEntryAsync()`.
+- `PublicShellStatus` separates process, shell state, main-window visibility, tray health, taskbar-entry health, and Public IPC readiness.
+- Launcher success/failure details must include coordinator pid, attempt id, host pid, Public IPC status, tray state, and taskbar usability when available.
+
+## Always-on tray and taskbar repair
+
+- The tray icon and menu are mandatory application-liveness indicators and are not controlled by user settings.
+- Tray watchdog starts during shell initialization and keeps running until application exit.
+- `ShowInTaskbar=true` means hidden/background states prefer `MinimizedToTaskbar`; it never disables the tray.
+- `ShowInTaskbar=false` is the only mode that may enter pure `TrayOnly`, and only after `TrayReady`.
+- When taskbar entry is requested but missing, shell repair recreates or shows the main window minimized with `ShowInTaskbar=true` while keeping the tray visible.
+
+## Regression coverage
+
+- Unit tests cover active coordinator rejection, stale heartbeat takeover, and host-pid assignment after a reserved attempt.
+- Manual QA still needs multi-process Launcher concurrency and real tray loss simulation on Windows.

.trae/specs/launcher-shell-hardening/startup-visuals-addendum.md

@@ -0,0 +1,37 @@
+# Launcher Slow-Startup And Startup Visual Addendum
+
+## New startup timing contract
+
+- `30s` is a soft timeout, not a failure threshold.
+- After `30s`, if the desktop process is still alive or Public IPC is connected, Launcher must stay in a waiting state and must not start another host process.
+- `120s` is the hard timeout.
+- Before returning `desktop_not_visible`, Launcher must attempt one foreground recovery through `ActivateMainWindowAsync()`.
+
+## Startup attempt de-duplication
+
+- Launcher persists the current startup attempt in `%LocalAppData%\LanMountainDesktop\.launcher\state\startup-attempt.json`.
+- A second Launcher process must attach to a live pending attempt instead of calling `Process.Start()` again.
+- Closing the splash window does not cancel startup; it transitions the attempt into detached waiting and preserves recovery state for the next Launcher run.
+
+## Startup visual modes
+
+- `EnableSlideTransition = true` forces `StartupVisualMode.SlideSplash` and automatically disables fade.
+- `EnableSlideTransition = false && EnableFadeTransition = false` resolves to `StartupVisualMode.StaticSplash`.
+- `EnableSlideTransition = false && EnableFadeTransition = true` resolves to `StartupVisualMode.Fade`.
+
+## UX safeguards
+
+- If the host process is still alive at failure time, the failure dialog must prefer:
+  - `Activate`
+  - `Wait`
+  - `Open Logs`
+  - `Exit`
+- Retry is only valid when Launcher is not about to create a duplicate desktop process.
+
+## Launcher coordinator guard
+
+- Startup attempts are now reserved before host launch, so concurrent Launchers cannot all reach `Process.Start()`.
+- A live coordinator is identified by `CoordinatorPid`, `CoordinatorPipeName`, and a heartbeat newer than `10s`.
+- Secondary Launchers send `activate-desktop` or `attach` to the coordinator pipe and then exit with the coordinator status.
+- If Host Public IPC is already available during a normal launch, Launcher activates the existing desktop and does not start a new host process.
+- Public shell status now reports tray readiness and taskbar-entry usability separately, allowing Launcher to distinguish "running but hidden" from "not recoverable".

LanMountainDesktop.Launcher/App.axaml.cs

@@ -1,3 +1,4 @@
+using System.Diagnostics;
 using Avalonia;
 using Avalonia.Controls;
 using Avalonia.Controls.ApplicationLifetimes;
@@ -5,7 +6,11 @@ using Avalonia.Markup.Xaml;
 using Avalonia.Threading;
 using LanMountainDesktop.Launcher.Models;
 using LanMountainDesktop.Launcher.Services;
+using LanMountainDesktop.Launcher.Services.Ipc;
 using LanMountainDesktop.Launcher.Views;
+using LanMountainDesktop.Shared.Contracts.Launcher;
+using LanMountainDesktop.Shared.IPC;
+using LanMountainDesktop.Shared.IPC.Abstractions.Services;
 
 namespace LanMountainDesktop.Launcher;
 
@@ -52,7 +57,7 @@ public partial class App : Application
             }
             else
             {
-                var splashWindow = new SplashWindow();
+                var splashWindow = CreateSplashWindow();
                 splashWindow.Show();
                 _ = RunCoordinatorWithSplashAsync(desktop, context, splashWindow);
             }
@@ -68,7 +73,7 @@ public partial class App : Application
             case "preview-splash":
             {
                 Logger.Info("Preview command: splash.");
-                var splashWindow = new SplashWindow();
+                var splashWindow = CreateSplashWindow();
                 splashWindow.SetDebugMode(true);
                 splashWindow.Show();
                 _ = SimulateSplashPreviewAsync(desktop, splashWindow);
@@ -112,6 +117,12 @@ public partial class App : Application
         }
     }
 
+    private static SplashWindow CreateSplashWindow()
+    {
+        var preferences = StartupVisualPreferencesResolver.Resolve();
+        return new SplashWindow(preferences.Mode);
+    }
+
     private async Task SimulateSplashPreviewAsync(IClassicDesktopStyleApplicationLifetime desktop, SplashWindow window)
     {
         var stages = new[] { "initializing", "update", "plugins", "launch", "ready" };
@@ -172,53 +183,281 @@ public partial class App : Application
         SplashWindow splashWindow)
     {
         LauncherResult result;
+        SplashWindow? currentSplashWindow = splashWindow;
+        var appRoot = Commands.ResolveAppRoot(context);
+        var startupAttemptRegistry = new StartupAttemptRegistry();
+        var coordinatorPipeName = LauncherCoordinatorIpcServer.CreatePipeName();
+        var successPolicy = LauncherFlowCoordinator.ResolveSuccessPolicyKey(context);
 
-        try
+        if (!startupAttemptRegistry.TryReserveCoordinator(
+                context.LaunchSource,
+                successPolicy,
+                coordinatorPipeName,
+                out var reservedAttempt,
+                out var activeCoordinatorAttempt))
         {
-            var appRoot = Commands.ResolveAppRoot(context);
-            Logger.Info(
-                $"Coordinator start. Command='{context.Command}'; AppRoot='{appRoot}'; " +
-                $"IsDebugMode={context.IsDebugMode}; LaunchSource='{context.LaunchSource}'; " +
-                $"ResultPath='{context.GetOption("result") ?? "<none>"}'.");
-
-            var deploymentLocator = new DeploymentLocator(appRoot);
-            var coordinator = new LauncherFlowCoordinator(
+            result = await AttachToExistingCoordinatorAsync(
                 context,
-                deploymentLocator,
-                new OobeStateService(appRoot),
-                new UpdateEngineService(deploymentLocator),
-                new PluginInstallerService());
+                currentSplashWindow,
+                activeCoordinatorAttempt).ConfigureAwait(false);
 
-            result = await coordinator.RunAsync(splashWindow).ConfigureAwait(false);
+            Logger.Info($"Secondary launcher completed. Success={result.Success}; Code='{result.Code}'.");
+            await WriteLauncherResultAsync(context, result).ConfigureAwait(false);
+
+            Environment.ExitCode = result.Success ? 0 : 1;
+            await Dispatcher.UIThread.InvokeAsync(() => desktop.Shutdown(Environment.ExitCode), DispatcherPriority.Background);
+            return;
         }
-        catch (Exception ex)
+
+        using var coordinatorServer = new LauncherCoordinatorIpcServer(
+            coordinatorPipeName,
+            BuildCoordinatorStatusFromAttempt(reservedAttempt),
+            HandleCoordinatorRequestAsync,
+            startupAttemptRegistry.UpdateOwnedCoordinatorHeartbeat);
+        coordinatorServer.Start();
+
+        while (true)
         {
-            Logger.Error("Coordinator threw an unhandled exception.", ex);
-            result = new LauncherResult
+            try
             {
-                Success = false,
-                Stage = "launch",
-                Code = "exception",
-                Message = $"Launcher failed: {ex.Message}",
-                ErrorMessage = ex.ToString()
-            };
+                Logger.Info(
+                    $"Coordinator start. Command='{context.Command}'; AppRoot='{appRoot}'; " +
+                    $"IsDebugMode={context.IsDebugMode}; LaunchSource='{context.LaunchSource}'; " +
+                    $"ResultPath='{context.GetOption("result") ?? "<none>"}'.");
+
+                var deploymentLocator = new DeploymentLocator(appRoot);
+                var coordinator = new LauncherFlowCoordinator(
+                    context,
+                    deploymentLocator,
+                    new OobeStateService(appRoot),
+                    new UpdateEngineService(deploymentLocator),
+                    new PluginInstallerService(),
+                    startupAttemptRegistry,
+                    coordinatorServer);
+
+                result = await coordinator.RunAsync(currentSplashWindow).ConfigureAwait(false);
+            }
+            catch (Exception ex)
+            {
+                Logger.Error("Coordinator threw an unhandled exception.", ex);
+                result = new LauncherResult
+                {
+                    Success = false,
+                    Stage = "launch",
+                    Code = "exception",
+                    Message = $"Launcher failed: {ex.Message}",
+                    ErrorMessage = ex.ToString()
+                };
+            }
+
+            if (result.Success ||
+                result.Code == "host_not_found" ||
+                (!string.Equals(result.Stage, "launch", StringComparison.OrdinalIgnoreCase) &&
+                 !string.Equals(result.Stage, "launchHost", StringComparison.OrdinalIgnoreCase)))
+            {
+                break;
+            }
+
+            var failureAction = await ShowFailureWindowAsync(result).ConfigureAwait(false);
+            if (failureAction == ErrorWindowResult.Exit)
+            {
+                break;
+            }
+
+            if (failureAction == ErrorWindowResult.ActivateExisting &&
+                await TryActivateExistingInstanceAsync().ConfigureAwait(false))
+            {
+                result = new LauncherResult
+                {
+                    Success = true,
+                    Stage = "launch",
+                    Code = "activation_requested",
+                    Message = "Launcher activated the existing desktop instance.",
+                    Details = result.Details
+                };
+                break;
+            }
+
+            currentSplashWindow = CreateSplashWindow();
+            currentSplashWindow.Show();
         }
 
         Logger.Info($"Coordinator completed. Success={result.Success}; Stage='{result.Stage}'; Code='{result.Code}'.");
         await WriteLauncherResultAsync(context, result).ConfigureAwait(false);
 
-        if (!result.Success &&
-            result.Code is not "host_not_found" &&
-            (string.Equals(result.Stage, "launch", StringComparison.OrdinalIgnoreCase) ||
-             string.Equals(result.Stage, "launchHost", StringComparison.OrdinalIgnoreCase)))
-        {
-            await ShowFailureWindowAsync(result).ConfigureAwait(false);
-        }
-
         Environment.ExitCode = result.Success ? 0 : 1;
         await Dispatcher.UIThread.InvokeAsync(() => desktop.Shutdown(Environment.ExitCode), DispatcherPriority.Background);
     }
 
+    private static async Task<LauncherResult> AttachToExistingCoordinatorAsync(
+        CommandContext context,
+        SplashWindow? splashWindow,
+        StartupAttemptRecord? activeCoordinatorAttempt)
+    {
+        var reporter = splashWindow as ISplashStageReporter;
+        reporter?.Report("activation", "Connecting to the active launcher...");
+
+        if (activeCoordinatorAttempt is not null &&
+            !string.IsNullOrWhiteSpace(activeCoordinatorAttempt.CoordinatorPipeName))
+        {
+            var command = string.Equals(context.LaunchSource, "restart", StringComparison.OrdinalIgnoreCase)
+                ? LauncherCoordinatorCommands.Attach
+                : LauncherCoordinatorCommands.ActivateDesktop;
+            var request = new LauncherCoordinatorRequest
+            {
+                Command = command,
+                LaunchSource = context.LaunchSource,
+                SuccessPolicy = LauncherFlowCoordinator.ResolveSuccessPolicyKey(context)
+            };
+
+            var response = await new LauncherCoordinatorIpcClient()
+                .SendAsync(activeCoordinatorAttempt.CoordinatorPipeName, request, TimeSpan.FromSeconds(2))
+                .ConfigureAwait(false);
+
+            if (response is not null)
+            {
+                reporter?.Report("activation", response.Message);
+                await DismissSplashIfNeededAsync(splashWindow).ConfigureAwait(false);
+                return new LauncherResult
+                {
+                    Success = response.Accepted,
+                    Stage = "launch",
+                    Code = response.Code,
+                    Message = response.Message,
+                    Details = BuildCoordinatorResultDetails(response.Status, response.ActivationResult)
+                };
+            }
+        }
+
+        var activation = await TryActivateExistingInstanceWithStatusAsync(TimeSpan.FromSeconds(2)).ConfigureAwait(false);
+        if (activation is not null)
+        {
+            reporter?.Report("activation", activation.Message);
+            await DismissSplashIfNeededAsync(splashWindow).ConfigureAwait(false);
+            return new LauncherResult
+            {
+                Success = activation.Accepted,
+                Stage = "launch",
+                Code = activation.Accepted ? "existing_host_activated" : "existing_host_activation_failed",
+                Message = activation.Message,
+                Details = BuildCoordinatorResultDetails(null, activation)
+            };
+        }
+
+        await DismissSplashIfNeededAsync(splashWindow).ConfigureAwait(false);
+        return new LauncherResult
+        {
+            Success = false,
+            Stage = "launch",
+            Code = "launcher_coordinator_unavailable",
+            Message = "Another Launcher is coordinating startup, but it did not respond in time.",
+            Details = new Dictionary<string, string>(StringComparer.OrdinalIgnoreCase)
+            {
+                ["activeCoordinatorPid"] = activeCoordinatorAttempt?.CoordinatorPid.ToString() ?? string.Empty,
+                ["activeCoordinatorPipeName"] = activeCoordinatorAttempt?.CoordinatorPipeName ?? string.Empty,
+                ["activeAttemptId"] = activeCoordinatorAttempt?.AttemptId ?? string.Empty,
+                ["activeHostPid"] = activeCoordinatorAttempt?.HostPid.ToString() ?? string.Empty
+            }
+        };
+    }
+
+    private static async Task<LauncherCoordinatorResponse> HandleCoordinatorRequestAsync(
+        LauncherCoordinatorRequest request,
+        LauncherCoordinatorStatus status)
+    {
+        if (string.Equals(request.Command, LauncherCoordinatorCommands.ActivateDesktop, StringComparison.OrdinalIgnoreCase))
+        {
+            var activation = await TryActivateExistingInstanceWithStatusAsync(TimeSpan.FromSeconds(2)).ConfigureAwait(false);
+            if (activation is not null)
+            {
+                return new LauncherCoordinatorResponse
+                {
+                    Accepted = activation.Accepted,
+                    Code = activation.Accepted ? "existing_host_activated" : "existing_host_activation_failed",
+                    Message = activation.Message,
+                    Status = status,
+                    ActivationResult = activation
+                };
+            }
+
+            return new LauncherCoordinatorResponse
+            {
+                Accepted = true,
+                Code = "attached_to_launcher_coordinator",
+                Message = "Attached to the active Launcher coordinator; desktop startup is still in progress.",
+                Status = status
+            };
+        }
+
+        return new LauncherCoordinatorResponse
+        {
+            Accepted = true,
+            Code = "attached_to_launcher_coordinator",
+            Message = "Attached to the active Launcher coordinator.",
+            Status = status
+        };
+    }
+
+    private static LauncherCoordinatorStatus BuildCoordinatorStatusFromAttempt(StartupAttemptRecord attempt)
+    {
+        return new LauncherCoordinatorStatus
+        {
+            AttemptId = attempt.AttemptId,
+            CoordinatorPid = Environment.ProcessId,
+            HostPid = attempt.HostPid,
+            HostProcessAlive = TryGetLiveProcess(attempt.HostPid),
+            LaunchSource = attempt.LaunchSource,
+            SuccessPolicy = attempt.SuccessPolicy,
+            LastObservedStage = attempt.LastObservedStage,
+            LastObservedMessage = attempt.LastObservedMessage,
+            PublicIpcConnected = attempt.PublicIpcConnected || attempt.IpcConnected,
+            State = attempt.State.ToString(),
+            SoftTimeoutShown = attempt.State is StartupAttemptState.SoftTimeout or StartupAttemptState.DetachedWaiting,
+            Completed = attempt.State is StartupAttemptState.Succeeded or StartupAttemptState.Failed,
+            Succeeded = attempt.State == StartupAttemptState.Succeeded,
+            UpdatedAtUtc = attempt.UpdatedAtUtc
+        };
+    }
+
+    private static Dictionary<string, string> BuildCoordinatorResultDetails(
+        LauncherCoordinatorStatus? status,
+        PublicShellActivationResult? activation)
+    {
+        var details = new Dictionary<string, string>(StringComparer.OrdinalIgnoreCase)
+        {
+            ["coordinatorPid"] = status?.CoordinatorPid.ToString() ?? string.Empty,
+            ["coordinatorAttemptId"] = status?.AttemptId ?? string.Empty,
+            ["hostPid"] = status?.HostPid.ToString() ?? activation?.Status.ProcessId.ToString() ?? string.Empty,
+            ["hostProcessAlive"] = status?.HostProcessAlive.ToString() ?? string.Empty,
+            ["publicIpcConnected"] = (status?.PublicIpcConnected ?? activation is not null).ToString(),
+            ["startupStage"] = status?.LastObservedStage.ToString() ?? string.Empty,
+            ["startupState"] = status?.State ?? string.Empty,
+            ["activationAccepted"] = activation?.Accepted.ToString() ?? string.Empty,
+            ["shellState"] = activation?.Status.ShellState ?? status?.ShellStatus?.ShellState ?? string.Empty,
+            ["trayState"] = activation?.Status.Tray.State ?? status?.ShellStatus?.Tray.State ?? string.Empty,
+            ["taskbarUsable"] = activation?.Status.Taskbar.IsUsable.ToString() ?? status?.ShellStatus?.Taskbar.IsUsable.ToString() ?? string.Empty
+        };
+
+        return details;
+    }
+
+    private static async Task DismissSplashIfNeededAsync(SplashWindow? splashWindow)
+    {
+        if (splashWindow is null)
+        {
+            return;
+        }
+
+        try
+        {
+            await splashWindow.DismissAsync().ConfigureAwait(false);
+        }
+        catch (Exception ex)
+        {
+            Logger.Warn($"Failed to dismiss splash after coordinator attach: {ex.Message}");
+        }
+    }
+
     private static async Task WriteLauncherResultAsync(CommandContext context, LauncherResult result)
     {
         var resultPath = context.GetOption("result");
@@ -238,15 +477,31 @@ public partial class App : Application
         }
     }
 
-    private static async Task ShowFailureWindowAsync(LauncherResult result)
+    private static async Task<ErrorWindowResult> ShowFailureWindowAsync(LauncherResult result)
     {
         ErrorWindow? errorWindow = null;
+        var hostProcessAlive = result.Details.TryGetValue("hostProcessAlive", out var hostProcessAliveText) &&
+                               bool.TryParse(hostProcessAliveText, out var hostProcessAliveValue) &&
+                               hostProcessAliveValue;
+        var hostPid = result.Details.TryGetValue("hostPid", out var hostPidText) &&
+                      int.TryParse(hostPidText, out var parsedPid)
+            ? parsedPid
+            : (int?)null;
 
         await Dispatcher.UIThread.InvokeAsync(() =>
         {
             try
             {
                 errorWindow = new ErrorWindow();
+                if (hostProcessAlive)
+                {
+                    errorWindow.ConfigureForRunningHostFailure(hostPid);
+                }
+                else
+                {
+                    errorWindow.ConfigureForGenericFailure(allowRetry: true);
+                }
+
                 errorWindow.SetErrorMessage(
                     $"Failed to start LanMountainDesktop.\n\nStage: {result.Stage}\nCode: {result.Code}\n\n{result.Message}");
                 errorWindow.Show();
@@ -259,16 +514,76 @@ public partial class App : Application
 
         if (errorWindow is null)
         {
-            return;
+            return ErrorWindowResult.Exit;
         }
 
         try
         {
-            await errorWindow.WaitForChoiceAsync().ConfigureAwait(false);
+            return await errorWindow.WaitForChoiceAsync().ConfigureAwait(false);
         }
         catch (Exception ex)
         {
             Logger.Error("Failure window closed unexpectedly.", ex);
+            return ErrorWindowResult.Exit;
+        }
+    }
+
+    private static async Task<bool> TryActivateExistingInstanceAsync()
+    {
+        var activation = await TryActivateExistingInstanceWithStatusAsync(TimeSpan.FromSeconds(5)).ConfigureAwait(false);
+        return activation?.Accepted == true;
+    }
+
+    private static async Task<PublicShellActivationResult?> TryActivateExistingInstanceWithStatusAsync(TimeSpan timeout)
+    {
+        try
+        {
+            using var ipcClient = new LanMountainDesktopIpcClient();
+            var connectTask = ipcClient.ConnectAsync();
+            var completedTask = await Task.WhenAny(connectTask, Task.Delay(timeout)).ConfigureAwait(false);
+            if (completedTask != connectTask)
+            {
+                return null;
+            }
+
+            await connectTask.ConfigureAwait(false);
+            if (!ipcClient.IsConnected)
+            {
+                return null;
+            }
+
+            var shellProxy = ipcClient.CreateProxy<IPublicShellControlService>();
+            var activationTask = shellProxy.ActivateMainWindowWithStatusAsync();
+            completedTask = await Task.WhenAny(activationTask, Task.Delay(timeout)).ConfigureAwait(false);
+            if (completedTask != activationTask)
+            {
+                return null;
+            }
+
+            return await activationTask.ConfigureAwait(false);
+        }
+        catch (Exception ex)
+        {
+            Logger.Warn($"Failed to activate the existing desktop instance: {ex.Message}");
+            return null;
+        }
+    }
+
+    private static bool TryGetLiveProcess(int processId)
+    {
+        if (processId <= 0)
+        {
+            return false;
+        }
+
+        try
+        {
+            using var process = Process.GetProcessById(processId);
+            return !process.HasExited;
+        }
+        catch
+        {
+            return false;
         }
     }
 

LanMountainDesktop.Launcher/AppJsonContext.cs

@@ -3,6 +3,7 @@ using System.Text.Json.Serialization;
 using LanMountainDesktop.Launcher.Models;
 using LanMountainDesktop.Launcher.Services;
 using LanMountainDesktop.Shared.Contracts.Launcher;
+using LanMountainDesktop.Shared.IPC.Abstractions.Services;
 
 namespace LanMountainDesktop.Launcher;
 
@@ -20,6 +21,13 @@ namespace LanMountainDesktop.Launcher;
 [JsonSerializable(typeof(SnapshotMetadata))]
 [JsonSerializable(typeof(AppVersionInfo))]
 [JsonSerializable(typeof(StartupProgressMessage))]
+[JsonSerializable(typeof(LauncherCoordinatorRequest))]
+[JsonSerializable(typeof(LauncherCoordinatorResponse))]
+[JsonSerializable(typeof(LauncherCoordinatorStatus))]
+[JsonSerializable(typeof(PublicShellStatus))]
+[JsonSerializable(typeof(PublicTrayStatus))]
+[JsonSerializable(typeof(PublicTaskbarStatus))]
+[JsonSerializable(typeof(PublicShellActivationResult))]
 [JsonSerializable(typeof(LauncherResult))]
 [JsonSerializable(typeof(HostDiscoveryConfig))]
 [JsonSerializable(typeof(PluginManifest))]

LanMountainDesktop.Launcher/LanMountainDesktop.Launcher.csproj

@@ -35,6 +35,7 @@
     <None Include="Assets\public-key.pem" CopyToOutputDirectory="PreserveNewest" />
     <!-- Avalonia 资源文件 -->
     <AvaloniaResource Include="Assets\logo.ico" />
+    <AvaloniaResource Include="..\LanMountainDesktop\Assets\logo_nightly.png" Link="Assets\logo_nightly.png" />
   </ItemGroup>
 
   <Target Name="CopyPublicKeyToLauncherDir" AfterTargets="Build">

LanMountainDesktop.Launcher/Models/LauncherCoordinatorMessages.cs

@@ -0,0 +1,96 @@
+using System.Text.Json.Serialization;
+using LanMountainDesktop.Shared.Contracts.Launcher;
+using LanMountainDesktop.Shared.IPC.Abstractions.Services;
+
+namespace LanMountainDesktop.Launcher.Models;
+
+internal static class LauncherCoordinatorCommands
+{
+    public const string Attach = "attach";
+    public const string ActivateDesktop = "activate-desktop";
+    public const string GetStatus = "get-status";
+}
+
+internal sealed class LauncherCoordinatorRequest
+{
+    [JsonPropertyName("requestId")]
+    public string RequestId { get; init; } = Guid.NewGuid().ToString("N");
+
+    [JsonPropertyName("command")]
+    public string Command { get; init; } = LauncherCoordinatorCommands.Attach;
+
+    [JsonPropertyName("launcherPid")]
+    public int LauncherPid { get; init; } = Environment.ProcessId;
+
+    [JsonPropertyName("launchSource")]
+    public string LaunchSource { get; init; } = string.Empty;
+
+    [JsonPropertyName("successPolicy")]
+    public string SuccessPolicy { get; init; } = string.Empty;
+}
+
+internal sealed class LauncherCoordinatorResponse
+{
+    [JsonPropertyName("accepted")]
+    public bool Accepted { get; init; }
+
+    [JsonPropertyName("code")]
+    public string Code { get; init; } = string.Empty;
+
+    [JsonPropertyName("message")]
+    public string Message { get; init; } = string.Empty;
+
+    [JsonPropertyName("status")]
+    public LauncherCoordinatorStatus? Status { get; init; }
+
+    [JsonPropertyName("activationResult")]
+    public PublicShellActivationResult? ActivationResult { get; init; }
+}
+
+internal sealed class LauncherCoordinatorStatus
+{
+    [JsonPropertyName("attemptId")]
+    public string AttemptId { get; init; } = string.Empty;
+
+    [JsonPropertyName("coordinatorPid")]
+    public int CoordinatorPid { get; init; } = Environment.ProcessId;
+
+    [JsonPropertyName("hostPid")]
+    public int HostPid { get; init; }
+
+    [JsonPropertyName("hostProcessAlive")]
+    public bool HostProcessAlive { get; init; }
+
+    [JsonPropertyName("launchSource")]
+    public string LaunchSource { get; init; } = string.Empty;
+
+    [JsonPropertyName("successPolicy")]
+    public string SuccessPolicy { get; init; } = string.Empty;
+
+    [JsonPropertyName("lastObservedStage")]
+    public StartupStage LastObservedStage { get; init; } = StartupStage.Initializing;
+
+    [JsonPropertyName("lastObservedMessage")]
+    public string LastObservedMessage { get; init; } = string.Empty;
+
+    [JsonPropertyName("publicIpcConnected")]
+    public bool PublicIpcConnected { get; init; }
+
+    [JsonPropertyName("state")]
+    public string State { get; init; } = string.Empty;
+
+    [JsonPropertyName("softTimeoutShown")]
+    public bool SoftTimeoutShown { get; init; }
+
+    [JsonPropertyName("completed")]
+    public bool Completed { get; init; }
+
+    [JsonPropertyName("succeeded")]
+    public bool Succeeded { get; init; }
+
+    [JsonPropertyName("shellStatus")]
+    public PublicShellStatus? ShellStatus { get; init; }
+
+    [JsonPropertyName("updatedAtUtc")]
+    public DateTimeOffset UpdatedAtUtc { get; init; } = DateTimeOffset.UtcNow;
+}

LanMountainDesktop.Launcher/Models/StartupAttemptRecord.cs

@@ -0,0 +1,64 @@
+using System.Text.Json.Serialization;
+using LanMountainDesktop.Shared.Contracts.Launcher;
+
+namespace LanMountainDesktop.Launcher.Models;
+
+internal enum StartupAttemptState
+{
+    Pending,
+    SoftTimeout,
+    DetachedWaiting,
+    Succeeded,
+    Failed
+}
+
+internal sealed class StartupAttemptRecord
+{
+    [JsonPropertyName("attemptId")]
+    public string AttemptId { get; set; } = Guid.NewGuid().ToString("N");
+
+    [JsonPropertyName("hostPid")]
+    public int HostPid { get; set; }
+
+    [JsonPropertyName("coordinatorPid")]
+    public int CoordinatorPid { get; set; }
+
+    [JsonPropertyName("coordinatorPipeName")]
+    public string CoordinatorPipeName { get; set; } = string.Empty;
+
+    [JsonPropertyName("startedAtUtc")]
+    public DateTimeOffset StartedAtUtc { get; set; } = DateTimeOffset.UtcNow;
+
+    [JsonPropertyName("updatedAtUtc")]
+    public DateTimeOffset UpdatedAtUtc { get; set; } = DateTimeOffset.UtcNow;
+
+    [JsonPropertyName("heartbeatAtUtc")]
+    public DateTimeOffset HeartbeatAtUtc { get; set; } = DateTimeOffset.UtcNow;
+
+    [JsonPropertyName("launchSource")]
+    public string LaunchSource { get; set; } = string.Empty;
+
+    [JsonPropertyName("successPolicy")]
+    public string SuccessPolicy { get; set; } = string.Empty;
+
+    [JsonPropertyName("lastObservedStage")]
+    public StartupStage LastObservedStage { get; set; } = StartupStage.Initializing;
+
+    [JsonPropertyName("lastObservedMessage")]
+    public string LastObservedMessage { get; set; } = string.Empty;
+
+    [JsonPropertyName("ipcConnected")]
+    public bool IpcConnected { get; set; }
+
+    [JsonPropertyName("publicIpcConnected")]
+    public bool PublicIpcConnected { get; set; }
+
+    [JsonPropertyName("shellStatus")]
+    public string ShellStatus { get; set; } = string.Empty;
+
+    [JsonPropertyName("reservedBeforeHostStart")]
+    public bool ReservedBeforeHostStart { get; set; }
+
+    [JsonPropertyName("state")]
+    public StartupAttemptState State { get; set; } = StartupAttemptState.Pending;
+}

LanMountainDesktop.Launcher/Services/Ipc/LauncherCoordinatorIpcClient.cs

@@ -0,0 +1,111 @@
+using System.IO.Pipes;
+using System.Text;
+using System.Text.Json;
+using LanMountainDesktop.Launcher.Models;
+
+namespace LanMountainDesktop.Launcher.Services.Ipc;
+
+internal sealed class LauncherCoordinatorIpcClient
+{
+    private const int LengthPrefixSize = 4;
+    private const int MaxPayloadLength = 1024 * 1024;
+
+    public async Task<LauncherCoordinatorResponse?> SendAsync(
+        string pipeName,
+        LauncherCoordinatorRequest request,
+        TimeSpan timeout)
+    {
+        if (string.IsNullOrWhiteSpace(pipeName))
+        {
+            return null;
+        }
+
+        using var timeoutCts = new CancellationTokenSource(timeout);
+        try
+        {
+            await using var client = new NamedPipeClientStream(
+                ".",
+                pipeName,
+                PipeDirection.InOut,
+                PipeOptions.Asynchronous);
+
+            await client.ConnectAsync(timeoutCts.Token).ConfigureAwait(false);
+            await WriteRequestAsync(client, request, timeoutCts.Token).ConfigureAwait(false);
+            return await ReadResponseAsync(client, timeoutCts.Token).ConfigureAwait(false);
+        }
+        catch (OperationCanceledException)
+        {
+            return null;
+        }
+        catch (TimeoutException)
+        {
+            return null;
+        }
+        catch (Exception ex)
+        {
+            Logger.Warn($"Failed to send launcher coordinator IPC request: {ex.Message}");
+            return null;
+        }
+    }
+
+    private static async Task WriteRequestAsync(
+        Stream stream,
+        LauncherCoordinatorRequest request,
+        CancellationToken cancellationToken)
+    {
+        var json = JsonSerializer.Serialize(request, AppJsonContext.Default.LauncherCoordinatorRequest);
+        var payload = Encoding.UTF8.GetBytes(json);
+        await stream.WriteAsync(BitConverter.GetBytes(payload.Length), cancellationToken).ConfigureAwait(false);
+        await stream.WriteAsync(payload, cancellationToken).ConfigureAwait(false);
+        await stream.FlushAsync(cancellationToken).ConfigureAwait(false);
+    }
+
+    private static async Task<LauncherCoordinatorResponse?> ReadResponseAsync(
+        Stream stream,
+        CancellationToken cancellationToken)
+    {
+        var lengthBuffer = new byte[LengthPrefixSize];
+        if (!await ReadExactAsync(stream, lengthBuffer, cancellationToken).ConfigureAwait(false))
+        {
+            return null;
+        }
+
+        var payloadLength = BitConverter.ToInt32(lengthBuffer, 0);
+        if (payloadLength <= 0 || payloadLength > MaxPayloadLength)
+        {
+            return null;
+        }
+
+        var payload = new byte[payloadLength];
+        if (!await ReadExactAsync(stream, payload, cancellationToken).ConfigureAwait(false))
+        {
+            return null;
+        }
+
+        return JsonSerializer.Deserialize(
+            Encoding.UTF8.GetString(payload),
+            AppJsonContext.Default.LauncherCoordinatorResponse);
+    }
+
+    private static async Task<bool> ReadExactAsync(
+        Stream stream,
+        byte[] buffer,
+        CancellationToken cancellationToken)
+    {
+        var totalRead = 0;
+        while (totalRead < buffer.Length)
+        {
+            var read = await stream
+                .ReadAsync(buffer.AsMemory(totalRead, buffer.Length - totalRead), cancellationToken)
+                .ConfigureAwait(false);
+            if (read == 0)
+            {
+                return false;
+            }
+
+            totalRead += read;
+        }
+
+        return true;
+    }
+}

LanMountainDesktop.Launcher/Services/Ipc/LauncherCoordinatorIpcServer.cs

@@ -0,0 +1,235 @@
+using System.Security.Cryptography;
+using System.Text;
+using System.Text.Json;
+using System.IO.Pipes;
+using LanMountainDesktop.Launcher.Models;
+
+namespace LanMountainDesktop.Launcher.Services.Ipc;
+
+internal sealed class LauncherCoordinatorIpcServer : IDisposable
+{
+    private const int LengthPrefixSize = 4;
+    private const int MaxPayloadLength = 1024 * 1024;
+    private readonly string _pipeName;
+    private readonly Func<LauncherCoordinatorRequest, LauncherCoordinatorStatus, Task<LauncherCoordinatorResponse>> _requestHandler;
+    private readonly Action<LauncherCoordinatorStatus> _heartbeatHandler;
+    private readonly CancellationTokenSource _cts = new();
+    private readonly object _statusGate = new();
+    private LauncherCoordinatorStatus _status;
+    private Task? _listenTask;
+    private Task? _heartbeatTask;
+
+    public LauncherCoordinatorIpcServer(
+        string pipeName,
+        LauncherCoordinatorStatus initialStatus,
+        Func<LauncherCoordinatorRequest, LauncherCoordinatorStatus, Task<LauncherCoordinatorResponse>> requestHandler,
+        Action<LauncherCoordinatorStatus> heartbeatHandler)
+    {
+        _pipeName = pipeName;
+        _status = initialStatus;
+        _requestHandler = requestHandler;
+        _heartbeatHandler = heartbeatHandler;
+    }
+
+    public static string CreatePipeName()
+    {
+        var seed = $"{Environment.UserName}:{Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData)}";
+        var bytes = SHA256.HashData(Encoding.UTF8.GetBytes(seed.ToLowerInvariant()));
+        return $"LanMountainDesktop_Launcher_Coordinator_{Convert.ToHexString(bytes[..8])}";
+    }
+
+    public void Start()
+    {
+        _listenTask ??= Task.Run(ListenLoopAsync);
+        _heartbeatTask ??= Task.Run(HeartbeatLoopAsync);
+    }
+
+    public LauncherCoordinatorStatus GetStatus()
+    {
+        lock (_statusGate)
+        {
+            return _status;
+        }
+    }
+
+    public void UpdateStatus(LauncherCoordinatorStatus status)
+    {
+        lock (_statusGate)
+        {
+            _status = status;
+        }
+    }
+
+    public void Dispose()
+    {
+        _cts.Cancel();
+
+        try
+        {
+            _listenTask?.Wait(TimeSpan.FromSeconds(1));
+            _heartbeatTask?.Wait(TimeSpan.FromSeconds(1));
+        }
+        catch
+        {
+        }
+
+        _cts.Dispose();
+    }
+
+    private async Task ListenLoopAsync()
+    {
+        while (!_cts.IsCancellationRequested)
+        {
+            NamedPipeServerStream? server = null;
+            try
+            {
+                server = new NamedPipeServerStream(
+                    _pipeName,
+                    PipeDirection.InOut,
+                    8,
+                    PipeTransmissionMode.Byte,
+                    PipeOptions.Asynchronous);
+
+                await server.WaitForConnectionAsync(_cts.Token).ConfigureAwait(false);
+                var connectedServer = server;
+                _ = Task.Run(() => HandleConnectionAsync(connectedServer, _cts.Token), _cts.Token);
+                server = null;
+            }
+            catch (OperationCanceledException)
+            {
+                break;
+            }
+            catch (Exception ex)
+            {
+                Logger.Warn($"Launcher coordinator IPC listener failed: {ex.Message}");
+                try
+                {
+                    await Task.Delay(250, _cts.Token).ConfigureAwait(false);
+                }
+                catch (OperationCanceledException)
+                {
+                    break;
+                }
+            }
+            finally
+            {
+                server?.Dispose();
+            }
+        }
+    }
+
+    private async Task HeartbeatLoopAsync()
+    {
+        while (!_cts.IsCancellationRequested)
+        {
+            try
+            {
+                _heartbeatHandler(GetStatus());
+                await Task.Delay(TimeSpan.FromSeconds(2), _cts.Token).ConfigureAwait(false);
+            }
+            catch (OperationCanceledException)
+            {
+                break;
+            }
+            catch (Exception ex)
+            {
+                Logger.Warn($"Launcher coordinator heartbeat failed: {ex.Message}");
+            }
+        }
+    }
+
+    private async Task HandleConnectionAsync(NamedPipeServerStream server, CancellationToken cancellationToken)
+    {
+        try
+        {
+            var request = await ReadRequestAsync(server, cancellationToken).ConfigureAwait(false);
+            var status = GetStatus();
+            var response = request is null
+                ? new LauncherCoordinatorResponse
+                {
+                    Accepted = false,
+                    Code = "invalid_request",
+                    Message = "Launcher coordinator request was invalid.",
+                    Status = status
+                }
+                : await _requestHandler(request, status).ConfigureAwait(false);
+
+            await WriteResponseAsync(server, response, cancellationToken).ConfigureAwait(false);
+        }
+        catch (Exception ex)
+        {
+            Logger.Warn($"Launcher coordinator IPC request failed: {ex.Message}");
+        }
+        finally
+        {
+            try
+            {
+                server.Dispose();
+            }
+            catch
+            {
+            }
+        }
+    }
+
+    private static async Task<LauncherCoordinatorRequest?> ReadRequestAsync(
+        Stream stream,
+        CancellationToken cancellationToken)
+    {
+        var lengthBuffer = new byte[LengthPrefixSize];
+        if (!await ReadExactAsync(stream, lengthBuffer, cancellationToken).ConfigureAwait(false))
+        {
+            return null;
+        }
+
+        var payloadLength = BitConverter.ToInt32(lengthBuffer, 0);
+        if (payloadLength <= 0 || payloadLength > MaxPayloadLength)
+        {
+            return null;
+        }
+
+        var payload = new byte[payloadLength];
+        if (!await ReadExactAsync(stream, payload, cancellationToken).ConfigureAwait(false))
+        {
+            return null;
+        }
+
+        return JsonSerializer.Deserialize(
+            Encoding.UTF8.GetString(payload),
+            AppJsonContext.Default.LauncherCoordinatorRequest);
+    }
+
+    private static async Task WriteResponseAsync(
+        Stream stream,
+        LauncherCoordinatorResponse response,
+        CancellationToken cancellationToken)
+    {
+        var json = JsonSerializer.Serialize(response, AppJsonContext.Default.LauncherCoordinatorResponse);
+        var payload = Encoding.UTF8.GetBytes(json);
+        await stream.WriteAsync(BitConverter.GetBytes(payload.Length), cancellationToken).ConfigureAwait(false);
+        await stream.WriteAsync(payload, cancellationToken).ConfigureAwait(false);
+        await stream.FlushAsync(cancellationToken).ConfigureAwait(false);
+    }
+
+    private static async Task<bool> ReadExactAsync(
+        Stream stream,
+        byte[] buffer,
+        CancellationToken cancellationToken)
+    {
+        var totalRead = 0;
+        while (totalRead < buffer.Length)
+        {
+            var read = await stream
+                .ReadAsync(buffer.AsMemory(totalRead, buffer.Length - totalRead), cancellationToken)
+                .ConfigureAwait(false);
+            if (read == 0)
+            {
+                return false;
+            }
+
+            totalRead += read;
+        }
+
+        return true;
+    }
+}

LanMountainDesktop.Launcher/Services/LauncherFlowCoordinator.cs

@@ -1,6 +1,7 @@
 using System.Diagnostics;
 using Avalonia.Threading;
 using LanMountainDesktop.Launcher.Models;
+using LanMountainDesktop.Launcher.Services.Ipc;
 using LanMountainDesktop.Launcher.Views;
 using LanMountainDesktop.Shared.Contracts.Launcher;
 using LanMountainDesktop.Shared.IPC;
@@ -10,6 +11,11 @@ namespace LanMountainDesktop.Launcher.Services;
 
 internal sealed class LauncherFlowCoordinator
 {
+    private static readonly TimeSpan StartupSoftTimeout = TimeSpan.FromSeconds(30);
+    private static readonly TimeSpan StartupHardTimeout = TimeSpan.FromSeconds(120);
+    private const string SoftTimeoutStatusMessage = "设备较慢，仍在启动，请稍候。";
+    private const string SoftTimeoutDetailsMessage = "桌面主进程仍在运行，Launcher 会继续等待，不会重复启动。";
+
     private static readonly string[] LauncherOnlyOptions =
     [
         "debug", "show-loading-details", "plugins-dir", "source", "result",
@@ -25,6 +31,8 @@ internal sealed class LauncherFlowCoordinator
     private readonly OobeStateService _oobeStateService;
     private readonly UpdateEngineService _updateEngine;
     private readonly PluginInstallerService _pluginInstallerService;
+    private readonly StartupAttemptRegistry _startupAttemptRegistry;
+    private readonly LauncherCoordinatorIpcServer? _coordinatorIpcServer;
     private readonly IReadOnlyList<IOobeStep> _oobeSteps;
 
     public LauncherFlowCoordinator(
@@ -32,16 +40,25 @@ internal sealed class LauncherFlowCoordinator
         DeploymentLocator deploymentLocator,
         OobeStateService oobeStateService,
         UpdateEngineService updateEngine,
-        PluginInstallerService pluginInstallerService)
+        PluginInstallerService pluginInstallerService,
+        StartupAttemptRegistry? startupAttemptRegistry = null,
+        LauncherCoordinatorIpcServer? coordinatorIpcServer = null)
     {
         _context = context;
         _deploymentLocator = deploymentLocator;
         _oobeStateService = oobeStateService;
         _updateEngine = updateEngine;
         _pluginInstallerService = pluginInstallerService;
+        _startupAttemptRegistry = startupAttemptRegistry ?? new StartupAttemptRegistry();
+        _coordinatorIpcServer = coordinatorIpcServer;
         _oobeSteps = [new WelcomeOobeStep(_oobeStateService, _context)];
     }
 
+    public static string ResolveSuccessPolicyKey(CommandContext context)
+    {
+        return new StartupSuccessTracker(context).PolicyKey;
+    }
+
     public async Task<LauncherResult> RunAsync(SplashWindow? existingSplashWindow = null)
     {
         try
@@ -66,6 +83,7 @@ internal sealed class LauncherFlowCoordinator
                 window.Show();
                 return window;
             });
+            var windowsClosingByCoordinator = false;
             var versionInfo = _deploymentLocator.GetVersionInfo();
             splashWindow.SetVersionInfo(versionInfo.Version, versionInfo.Codename);
             var reporter = (ISplashStageReporter)splashWindow;
@@ -85,8 +103,63 @@ internal sealed class LauncherFlowCoordinator
             var lastStage = StartupStage.Initializing;
             var lastStageMessage = "launcher-started";
             var startupSuccessTracker = new StartupSuccessTracker(_context);
+            var activationFailureReason = string.Empty;
+            var ipcConnected = false;
+            var softTimeoutShown = false;
+            var attachedToExistingAttempt = false;
+            StartupAttemptRecord? trackedAttempt = null;
+            PublicShellStatus? shellStatus = null;
+
+            void PublishCoordinatorStatus(bool? hostProcessAliveOverride = null, bool completed = false, bool succeeded = false)
+            {
+                if (_coordinatorIpcServer is null)
+                {
+                    return;
+                }
+
+                trackedAttempt = _startupAttemptRegistry.GetOwnedAttempt() ?? trackedAttempt;
+                var hostPid = trackedAttempt?.HostPid ?? 0;
+                var hostProcessAlive = hostProcessAliveOverride ??
+                                       (hostPid > 0 && TryGetLiveProcess(hostPid, out _));
+                var status = new LauncherCoordinatorStatus
+                {
+                    AttemptId = trackedAttempt?.AttemptId ?? string.Empty,
+                    CoordinatorPid = Environment.ProcessId,
+                    HostPid = hostPid,
+                    HostProcessAlive = hostProcessAlive,
+                    LaunchSource = trackedAttempt?.LaunchSource ?? _context.LaunchSource,
+                    SuccessPolicy = trackedAttempt?.SuccessPolicy ?? startupSuccessTracker.PolicyKey,
+                    LastObservedStage = lastStage,
+                    LastObservedMessage = lastStageMessage,
+                    PublicIpcConnected = ipcConnected,
+                    State = trackedAttempt?.State.ToString() ?? StartupAttemptState.Pending.ToString(),
+                    SoftTimeoutShown = softTimeoutShown,
+                    Completed = completed,
+                    Succeeded = succeeded,
+                    ShellStatus = shellStatus,
+                    UpdatedAtUtc = DateTimeOffset.UtcNow
+                };
+
+                _coordinatorIpcServer.UpdateStatus(status);
+                _startupAttemptRegistry.UpdateOwnedCoordinatorHeartbeat(status);
+            }
+
+            trackedAttempt = _startupAttemptRegistry.GetOwnedAttempt();
+            PublishCoordinatorStatus();
 
             var loadingState = new LoadingStateMessage();
+            EventHandler? splashClosedHandler = null;
+            splashClosedHandler = (_, _) =>
+            {
+                if (windowsClosingByCoordinator)
+                {
+                    return;
+                }
+
+                _startupAttemptRegistry.MarkOwnedDetachedWaiting();
+                Logger.Warn("Splash window was closed manually. Launcher will continue monitoring the current startup attempt.");
+            };
+            splashWindow.Closed += splashClosedHandler;
             using var ipcClient = new LanMountainDesktopIpcClient();
             ipcClient.RegisterNotifyHandler<StartupProgressMessage>(IpcRoutedNotifyIds.LauncherStartupProgress, message =>
             {
@@ -94,8 +167,9 @@ internal sealed class LauncherFlowCoordinator
                 {
                     try
                     {
+                        ipcConnected = true;
                         lastStage = message.Stage;
-                        lastStageMessage = message.Message ?? string.Empty;
+                        lastStageMessage = message.Message ?? message.Stage.ToString();
                         Logger.Info($"IPC stage received. Stage='{message.Stage}'; Message='{message.Message ?? string.Empty}'.");
 
                         loadingState = loadingState with
@@ -108,6 +182,8 @@ internal sealed class LauncherFlowCoordinator
 
                         reporter.Report(MapStartupStageToSplashStage(message.Stage), message.Message ?? message.Stage.ToString());
                         loadingDetailsWindow?.UpdateLoadingState(loadingState);
+                        _startupAttemptRegistry.UpdateOwnedStage(message.Stage, message.Message, ipcConnected: true);
+                        PublishCoordinatorStatus();
 
                         if (startupSuccessTracker.TryResolve(message.Stage, out var successState))
                         {
@@ -116,6 +192,7 @@ internal sealed class LauncherFlowCoordinator
 
                         if (message.Stage == StartupStage.ActivationFailed)
                         {
+                            activationFailureReason = message.Message ?? "activation_failed";
                             activationFailedTcs.TrySetResult(message.Message ?? "activation_failed");
                         }
                     }
@@ -143,6 +220,51 @@ internal sealed class LauncherFlowCoordinator
 
             try
             {
+                if (ShouldProbeExistingHostBeforeLaunch(_context))
+                {
+                    var existingActivation = await TryActivateExistingHostWithStatusAsync(ipcClient, TimeSpan.FromMilliseconds(900))
+                        .ConfigureAwait(false);
+                    if (existingActivation is not null)
+                    {
+                        ipcConnected = true;
+                        shellStatus = existingActivation.Status;
+                        lastStage = existingActivation.Accepted
+                            ? StartupStage.ActivationRedirected
+                            : StartupStage.ActivationFailed;
+                        lastStageMessage = existingActivation.Message;
+                        if (existingActivation.Accepted)
+                        {
+                            _startupAttemptRegistry.MarkOwnedSucceeded(lastStage, lastStageMessage);
+                        }
+                        else
+                        {
+                            _startupAttemptRegistry.MarkOwnedFailed(lastStage, lastStageMessage);
+                        }
+
+                        PublishCoordinatorStatus(
+                            hostProcessAliveOverride: true,
+                            completed: true,
+                            succeeded: existingActivation.Accepted);
+                        windowsClosingByCoordinator = true;
+                        await CloseWindowsAsync(splashWindow, loadingDetailsWindow).ConfigureAwait(false);
+                        return BuildResult(
+                            success: existingActivation.Accepted,
+                            stage: "launch",
+                            code: existingActivation.Accepted ? "existing_host_activated" : "existing_host_activation_failed",
+                            message: existingActivation.Message,
+                            details: MergeDetails(
+                                launcherContextDetails,
+                                new Dictionary<string, string>(StringComparer.OrdinalIgnoreCase)
+                                {
+                                    ["publicIpcConnected"] = "true",
+                                    ["existingHostPid"] = existingActivation.Status.ProcessId.ToString(),
+                                    ["existingShellState"] = existingActivation.Status.ShellState,
+                                    ["existingTrayState"] = existingActivation.Status.Tray.State,
+                                    ["existingTaskbarUsable"] = existingActivation.Status.Taskbar.IsUsable.ToString()
+                                }));
+                    }
+                }
+
                 reporter.Report("update", "Checking updates...");
                 var updateResult = await _updateEngine.ApplyPendingUpdateAsync().ConfigureAwait(false);
                 if (!updateResult.Success)
@@ -170,7 +292,91 @@ internal sealed class LauncherFlowCoordinator
                 }
 
                 reporter.Report("launch", "Launching desktop...");
-                var launchOutcome = await LaunchHostWithIpcAsync().ConfigureAwait(false);
+                var launchOutcome = default(HostLaunchOutcome);
+                var attachableAttempt = _startupAttemptRegistry.TryGetAttachableAttempt(_context.LaunchSource, startupSuccessTracker.PolicyKey);
+                if (attachableAttempt is not null &&
+                    _startupAttemptRegistry.AdoptAttempt(attachableAttempt.AttemptId) &&
+                    TryGetLiveProcess(attachableAttempt.HostPid, out var attachedProcess))
+                {
+                    trackedAttempt = attachableAttempt;
+                    attachedToExistingAttempt = true;
+                    ipcConnected = attachableAttempt.IpcConnected;
+                    lastStage = attachableAttempt.LastObservedStage;
+                    lastStageMessage = string.IsNullOrWhiteSpace(attachableAttempt.LastObservedMessage)
+                        ? "Attached to the existing startup attempt."
+                        : attachableAttempt.LastObservedMessage;
+                    reporter.Report(MapStartupStageToSplashStage(lastStage), lastStageMessage);
+                    PublishCoordinatorStatus(hostProcessAliveOverride: true);
+
+                    if (startupSuccessTracker.TryResolve(lastStage, out var attachedSuccessState))
+                    {
+                        windowsClosingByCoordinator = true;
+                        _startupAttemptRegistry.MarkOwnedSucceeded(attachedSuccessState.Stage, attachedSuccessState.Message);
+                        await CloseWindowsAsync(splashWindow, loadingDetailsWindow).ConfigureAwait(false);
+                        return BuildResult(
+                            success: true,
+                            stage: "launch",
+                            code: attachedSuccessState.Code,
+                            message: attachedSuccessState.Message,
+                            details: MergeDetails(
+                                launcherContextDetails,
+                                BuildAttemptDetails(
+                                    trackedAttempt,
+                                    attachedToExistingAttempt,
+                                    ipcConnected,
+                                    hostProcessAlive: true,
+                                    lastStage,
+                                    lastStageMessage,
+                                    activationFailureReason,
+                                    softTimeoutShown: false,
+                                    recoveryActivationAttempted: false)));
+                    }
+
+                    if (attachableAttempt.State is StartupAttemptState.SoftTimeout or StartupAttemptState.DetachedWaiting)
+                    {
+                        softTimeoutShown = true;
+                        reporter.Report("delayed", SoftTimeoutStatusMessage);
+                        loadingState = BuildDelayedLoadingState(
+                            loadingState,
+                            SoftTimeoutStatusMessage,
+                            SoftTimeoutDetailsMessage,
+                            trackedAttempt.StartedAtUtc);
+                        loadingDetailsWindow?.UpdateLoadingState(loadingState);
+                    }
+
+                    launchOutcome = HostLaunchOutcome.FromProcess(
+                        attachedProcess!,
+                        BuildResult(
+                            true,
+                            "launchHost",
+                            "attached_attempt",
+                            "Attached to an existing startup attempt.",
+                            BuildAttemptDetails(
+                                trackedAttempt,
+                                attachedToExistingAttempt,
+                                ipcConnected,
+                                hostProcessAlive: true,
+                                lastStage,
+                                lastStageMessage,
+                                activationFailureReason,
+                                softTimeoutShown,
+                                recoveryActivationAttempted: false)),
+                        BuildAttemptDetails(
+                            trackedAttempt,
+                            attachedToExistingAttempt,
+                            ipcConnected,
+                            hostProcessAlive: true,
+                            lastStage,
+                            lastStageMessage,
+                            activationFailureReason,
+                            softTimeoutShown,
+                            recoveryActivationAttempted: false));
+                }
+                else
+                {
+                    launchOutcome = await LaunchHostWithIpcAsync().ConfigureAwait(false);
+                }
+
                 if (!launchOutcome.Result.Success)
                 {
                     return WithAdditionalDetails(launchOutcome.Result, launcherContextDetails);
@@ -189,7 +395,37 @@ internal sealed class LauncherFlowCoordinator
                         stage: "launch",
                         code: "host_start_failed",
                         message: "Host launch did not create a process.",
-                        details: MergeDetails(launcherContextDetails, launchOutcome.Details));
+                        details: MergeDetails(
+                            launcherContextDetails,
+                            MergeDetails(
+                                launchOutcome.Details,
+                                BuildAttemptDetails(
+                                    trackedAttempt,
+                                    attachedToExistingAttempt,
+                                    ipcConnected,
+                                    hostProcessAlive: false,
+                                    lastStage,
+                                    lastStageMessage,
+                                    activationFailureReason,
+                                    softTimeoutShown,
+                                    recoveryActivationAttempted: false))));
+                }
+
+                if (!attachedToExistingAttempt)
+                {
+                    var reservedAttempt = _startupAttemptRegistry.GetOwnedAttempt();
+                    trackedAttempt = reservedAttempt is { ReservedBeforeHostStart: true }
+                        ? _startupAttemptRegistry.AssignOwnedHostProcess(
+                            launchOutcome.Process.Id,
+                            lastStage,
+                            lastStageMessage)
+                        : _startupAttemptRegistry.StartOwnedAttempt(
+                            launchOutcome.Process.Id,
+                            _context.LaunchSource,
+                            startupSuccessTracker.PolicyKey,
+                            lastStage,
+                            lastStageMessage);
+                    PublishCoordinatorStatus(hostProcessAliveOverride: true);
                 }
 
                 var connected = await TryConnectToPublicIpcAsync(ipcClient, TimeSpan.FromSeconds(5)).ConfigureAwait(false);
@@ -197,68 +433,182 @@ internal sealed class LauncherFlowCoordinator
                 {
                     Logger.Warn("Timed out waiting for host public IPC. Launcher will continue without live startup notifications.");
                 }
+                else
+                {
+                    ipcConnected = true;
+                    _startupAttemptRegistry.MarkOwnedIpcConnected();
+                    shellStatus = await TryGetPublicShellStatusAsync(ipcClient).ConfigureAwait(false);
+                    PublishCoordinatorStatus(hostProcessAliveOverride: true);
+                }
+
+                Dictionary<string, string> ComposeLaunchDetails(bool hostProcessAlive, bool recoveryActivationAttempted = false)
+                {
+                    return MergeDetails(
+                        launcherContextDetails,
+                        MergeDetails(
+                            launchOutcome.Details,
+                            BuildAttemptDetails(
+                                trackedAttempt,
+                                attachedToExistingAttempt,
+                                ipcConnected,
+                                hostProcessAlive,
+                                lastStage,
+                                lastStageMessage,
+                                activationFailureReason,
+                                softTimeoutShown,
+                                recoveryActivationAttempted)));
+                }
 
                 var processExitTask = launchOutcome.Process.WaitForExitAsync();
-                var completedTask = await Task.WhenAny(
-                    successTcs.Task,
-                    activationFailedTcs.Task,
-                    processExitTask,
-                    Task.Delay(TimeSpan.FromSeconds(30))).ConfigureAwait(false);
+                var startedAt = trackedAttempt?.StartedAtUtc ?? DateTimeOffset.UtcNow;
+                var softTimeoutAt = startedAt + StartupSoftTimeout;
+                var hardTimeoutAt = startedAt + StartupHardTimeout;
+                var nextReconnectAttemptAt = DateTimeOffset.UtcNow.AddSeconds(5);
 
-                if (completedTask == successTcs.Task)
+                while (true)
                 {
-                    var successState = await successTcs.Task.ConfigureAwait(false);
-                    await CloseWindowsAsync(splashWindow, loadingDetailsWindow).ConfigureAwait(false);
-                    return BuildResult(
-                        success: true,
-                        stage: "launch",
-                        code: successState.Code,
-                        message: successState.Message,
-                        details: MergeDetails(launcherContextDetails, launchOutcome.Details));
-                }
-
-                if (completedTask == activationFailedTcs.Task)
-                {
-                    Logger.Warn($"Activation failure received before desktop visibility. Reason='{await activationFailedTcs.Task.ConfigureAwait(false)}'.");
-                    var retryOutcome = await RetryActivationAfterEarlyFailureAsync().ConfigureAwait(false);
-                    if (retryOutcome is not null)
+                    if (successTcs.Task.IsCompleted)
                     {
+                        var successState = await successTcs.Task.ConfigureAwait(false);
+                        windowsClosingByCoordinator = true;
+                        _startupAttemptRegistry.MarkOwnedSucceeded(successState.Stage, successState.Message);
+                        PublishCoordinatorStatus(!launchOutcome.Process.HasExited, completed: true, succeeded: true);
                         await CloseWindowsAsync(splashWindow, loadingDetailsWindow).ConfigureAwait(false);
-                        return WithAdditionalDetails(retryOutcome, launcherContextDetails);
+                        return BuildResult(
+                            success: true,
+                            stage: "launch",
+                            code: successState.Code,
+                            message: successState.Message,
+                            details: ComposeLaunchDetails(!launchOutcome.Process.HasExited));
                     }
+
+                    if (activationFailedTcs.Task.IsCompleted && string.IsNullOrWhiteSpace(activationFailureReason))
+                    {
+                        activationFailureReason = await activationFailedTcs.Task.ConfigureAwait(false);
+                        Logger.Warn($"Activation failure received before startup success. Reason='{activationFailureReason}'.");
+                    }
+
+                    if (processExitTask.IsCompleted)
+                    {
+                        var exitCode = launchOutcome.Process.ExitCode;
+                        Logger.Warn($"Host exited before startup success criteria were met. ExitCode={exitCode}.");
+
+                        windowsClosingByCoordinator = true;
+                        if (exitCode == HostExitCodes.SecondaryActivationSucceeded)
+                        {
+                            _startupAttemptRegistry.MarkOwnedSucceeded(StartupStage.ActivationRedirected, "Host redirected activation to the existing desktop instance.");
+                            PublishCoordinatorStatus(hostProcessAliveOverride: false, completed: true, succeeded: true);
+                            await CloseWindowsAsync(splashWindow, loadingDetailsWindow).ConfigureAwait(false);
+                            return BuildResult(
+                                success: true,
+                                stage: "launch",
+                                code: "activation_redirected",
+                                message: "Host redirected activation to the existing desktop instance.",
+                                details: MergeDetails(
+                                    ComposeLaunchDetails(hostProcessAlive: false),
+                                    new Dictionary<string, string>(StringComparer.OrdinalIgnoreCase)
+                                    {
+                                        ["exitCode"] = exitCode.ToString()
+                                    }));
+                        }
+
+                        _startupAttemptRegistry.MarkOwnedFailed(lastStage, activationFailureReason);
+                        PublishCoordinatorStatus(hostProcessAliveOverride: false, completed: true, succeeded: false);
+                        await CloseWindowsAsync(splashWindow, loadingDetailsWindow).ConfigureAwait(false);
+                        return BuildResult(
+                            success: false,
+                            stage: "launch",
+                            code: exitCode is HostExitCodes.SecondaryActivationFailed or HostExitCodes.RestartLockNotAcquired
+                                ? "activation_failed"
+                                : "host_exited_early",
+                            message: exitCode is HostExitCodes.SecondaryActivationFailed or HostExitCodes.RestartLockNotAcquired
+                                ? $"Host activation handshake failed before the required startup state was reported. ExitCode={exitCode}."
+                                : $"Host exited before the required startup state was reported. ExitCode={exitCode}.",
+                            details: MergeDetails(
+                                ComposeLaunchDetails(hostProcessAlive: false),
+                                new Dictionary<string, string>(StringComparer.OrdinalIgnoreCase)
+                                {
+                                    ["exitCode"] = exitCode.ToString()
+                                }));
+                    }
+
+                    var now = DateTimeOffset.UtcNow;
+                    if (!ipcConnected &&
+                        !launchOutcome.Process.HasExited &&
+                        now >= nextReconnectAttemptAt)
+                    {
+                        connected = await TryConnectToPublicIpcAsync(ipcClient, TimeSpan.FromMilliseconds(800)).ConfigureAwait(false);
+                        if (connected)
+                        {
+                            ipcConnected = true;
+                            _startupAttemptRegistry.MarkOwnedIpcConnected();
+                            shellStatus = await TryGetPublicShellStatusAsync(ipcClient).ConfigureAwait(false);
+                            PublishCoordinatorStatus(hostProcessAliveOverride: true);
+                        }
+
+                        nextReconnectAttemptAt = DateTimeOffset.UtcNow.AddSeconds(5);
+                    }
+
+                    if (!softTimeoutShown &&
+                        now >= softTimeoutAt &&
+                        (!launchOutcome.Process.HasExited || ipcConnected))
+                    {
+                        softTimeoutShown = true;
+                        _startupAttemptRegistry.MarkOwnedSoftTimeout(SoftTimeoutStatusMessage);
+                        reporter.Report("delayed", SoftTimeoutStatusMessage);
+                        loadingState = BuildDelayedLoadingState(
+                            loadingState,
+                            SoftTimeoutStatusMessage,
+                            SoftTimeoutDetailsMessage,
+                            trackedAttempt?.StartedAtUtc ?? startedAt);
+                        loadingDetailsWindow?.UpdateLoadingState(loadingState);
+                        PublishCoordinatorStatus(hostProcessAliveOverride: !launchOutcome.Process.HasExited);
+                    }
+
+                    if (now >= hardTimeoutAt)
+                    {
+                        break;
+                    }
+
+                    var nextCheckpointAt = hardTimeoutAt;
+                    if (!softTimeoutShown && softTimeoutAt < nextCheckpointAt)
+                    {
+                        nextCheckpointAt = softTimeoutAt;
+                    }
+
+                    var delay = nextCheckpointAt - now;
+                    if (delay > TimeSpan.FromSeconds(1))
+                    {
+                        delay = TimeSpan.FromSeconds(1);
+                    }
+                    else if (delay < TimeSpan.FromMilliseconds(100))
+                    {
+                        delay = TimeSpan.FromMilliseconds(100);
+                    }
+
+                    await Task.WhenAny(
+                        successTcs.Task,
+                        activationFailedTcs.Task,
+                        processExitTask,
+                        Task.Delay(delay)).ConfigureAwait(false);
                 }
 
-                if (completedTask == processExitTask)
+                var recoveryActivationAttempted = false;
+                if (!connected && !launchOutcome.Process.HasExited)
                 {
-                    var exitCode = launchOutcome.Process.ExitCode;
-                    Logger.Warn($"Host exited before startup success criteria were met. ExitCode={exitCode}.");
-
-                    if (exitCode is HostExitCodes.SecondaryActivationFailed or HostExitCodes.RestartLockNotAcquired)
+                    connected = await TryConnectToPublicIpcAsync(ipcClient, TimeSpan.FromSeconds(1)).ConfigureAwait(false);
+                    if (connected)
                     {
-                        var retryOutcome = await RetryActivationAfterEarlyFailureAsync().ConfigureAwait(false);
-                        if (retryOutcome is not null)
-                        {
-                            await CloseWindowsAsync(splashWindow, loadingDetailsWindow).ConfigureAwait(false);
-                            return WithAdditionalDetails(retryOutcome, launcherContextDetails);
-                        }
+                        ipcConnected = true;
+                        _startupAttemptRegistry.MarkOwnedIpcConnected();
+                        shellStatus = await TryGetPublicShellStatusAsync(ipcClient).ConfigureAwait(false);
+                        PublishCoordinatorStatus(hostProcessAliveOverride: true);
                     }
-
-                    await CloseWindowsAsync(splashWindow, loadingDetailsWindow).ConfigureAwait(false);
-                    return BuildResult(
-                        success: false,
-                        stage: "launch",
-                        code: exitCode == HostExitCodes.SecondaryActivationSucceeded ? "activation_redirected" : "host_exited_early",
-                        message: exitCode == HostExitCodes.SecondaryActivationSucceeded
-                            ? "Host redirected activation to the existing desktop instance."
-                            : $"Host exited before the required startup state was reported. ExitCode={exitCode}.",
-                        details: MergeDetails(launcherContextDetails, MergeDetails(launchOutcome.Details, new Dictionary<string, string>
-                        {
-                            ["exitCode"] = exitCode.ToString()
-                        })));
                 }
 
                 if (connected && !launchOutcome.Process.HasExited)
                 {
+                    recoveryActivationAttempted = true;
                     var recoveryOutcome = await TryRecoverWithPublicActivationAsync(
                         ipcClient,
                         launchOutcome.Process,
@@ -266,48 +616,60 @@ internal sealed class LauncherFlowCoordinator
                         startupSuccessTracker).ConfigureAwait(false);
                     if (recoveryOutcome is not null)
                     {
+                        windowsClosingByCoordinator = true;
+                        _startupAttemptRegistry.MarkOwnedSucceeded(recoveryOutcome.Stage, recoveryOutcome.Message);
+                        shellStatus = await TryGetPublicShellStatusAsync(ipcClient).ConfigureAwait(false);
+                        PublishCoordinatorStatus(!launchOutcome.Process.HasExited, completed: true, succeeded: true);
                         await CloseWindowsAsync(splashWindow, loadingDetailsWindow).ConfigureAwait(false);
                         return BuildResult(
                             success: true,
                             stage: "launch",
                             code: recoveryOutcome.Code,
                             message: recoveryOutcome.Message,
-                            details: MergeDetails(launcherContextDetails, MergeDetails(launchOutcome.Details, new Dictionary<string, string>
-                            {
-                                ["recoveryActivationAttempted"] = bool.TrueString
-                            })));
+                            details: ComposeLaunchDetails(
+                                !launchOutcome.Process.HasExited,
+                                recoveryActivationAttempted: true));
                     }
                 }
 
+                windowsClosingByCoordinator = true;
+                _startupAttemptRegistry.MarkOwnedFailed(lastStage, activationFailureReason);
+                PublishCoordinatorStatus(!launchOutcome.Process.HasExited, completed: true, succeeded: false);
                 await CloseWindowsAsync(splashWindow, loadingDetailsWindow).ConfigureAwait(false);
                 return BuildResult(
                     success: false,
                     stage: "launch",
                     code: "desktop_not_visible",
-                    message: "Host process started, but it never reached the required startup state within 30 seconds.",
-                    details: MergeDetails(launcherContextDetails, MergeDetails(launchOutcome.Details, new Dictionary<string, string>
-                    {
-                        ["ipcStage"] = lastStage.ToString(),
-                        ["ipcMessage"] = lastStageMessage
-                    })));
+                    message: "Host process started, but it never reached the required startup state within 120 seconds.",
+                    details: ComposeLaunchDetails(
+                        !launchOutcome.Process.HasExited,
+                        recoveryActivationAttempted));
             }
             finally
             {
-                await Dispatcher.UIThread.InvokeAsync(() =>
+                if (splashClosedHandler is not null)
                 {
-                    try
+                    splashWindow.Closed -= splashClosedHandler;
+                }
+
+                if (!windowsClosingByCoordinator)
+                {
+                    await Dispatcher.UIThread.InvokeAsync(() =>
                     {
-                        if (splashWindow.IsVisible && splashWindow.IsLoaded)
+                        try
                         {
-                            splashWindow.Close();
-                            Logger.Info("Splash window closed in coordinator cleanup.");
+                            if (splashWindow.IsVisible && splashWindow.IsLoaded)
+                            {
+                                splashWindow.Close();
+                                Logger.Info("Splash window closed in coordinator cleanup.");
+                            }
                         }
-                    }
-                    catch (Exception ex)
-                    {
-                        Logger.Error("Failed to close splash window during coordinator cleanup.", ex);
-                    }
-                });
+                        catch (Exception ex)
+                        {
+                            Logger.Error("Failed to close splash window during coordinator cleanup.", ex);
+                        }
+                    });
+                }
             }
         }
         catch (Exception ex)
@@ -373,20 +735,17 @@ internal sealed class LauncherFlowCoordinator
 
     private static async Task CloseWindowsAsync(SplashWindow splashWindow, LoadingDetailsWindow? loadingDetailsWindow)
     {
+        try
+        {
+            await splashWindow.DismissAsync().ConfigureAwait(false);
+        }
+        catch (Exception ex)
+        {
+            Logger.Error("Failed to dismiss splash window.", ex);
+        }
+
         await Dispatcher.UIThread.InvokeAsync(() =>
         {
-            try
-            {
-                if (splashWindow.IsVisible && splashWindow.IsLoaded)
-                {
-                    splashWindow.Close();
-                }
-            }
-            catch (Exception ex)
-            {
-                Logger.Error("Failed to close splash window.", ex);
-            }
-
             try
             {
                 if (loadingDetailsWindow is not null && loadingDetailsWindow.IsVisible)
@@ -672,6 +1031,7 @@ internal sealed class LauncherFlowCoordinator
             try
             {
                 errorWindow = new ErrorWindow();
+                errorWindow.ConfigureForHostNotFound();
                 errorWindow.SetErrorMessage("LanMountainDesktop host executable was not found.");
                 errorWindow.Show();
                 Logger.Warn("Host not found. Showing error window.");
@@ -955,6 +1315,11 @@ internal sealed class LauncherFlowCoordinator
         LanMountainDesktopIpcClient ipcClient,
         TimeSpan timeout)
     {
+        if (ipcClient.IsConnected)
+        {
+            return true;
+        }
+
         var connectTask = ipcClient.ConnectAsync();
         var completedTask = await Task.WhenAny(connectTask, Task.Delay(timeout)).ConfigureAwait(false);
         if (completedTask != connectTask)
@@ -966,6 +1331,59 @@ internal sealed class LauncherFlowCoordinator
         return true;
     }
 
+    private static bool ShouldProbeExistingHostBeforeLaunch(CommandContext context)
+    {
+        if (!string.Equals(context.Command, "launch", StringComparison.OrdinalIgnoreCase))
+        {
+            return false;
+        }
+
+        if (context.IsPreviewCommand || context.IsMaintenanceCommand)
+        {
+            return false;
+        }
+
+        return !string.Equals(context.LaunchSource, "restart", StringComparison.OrdinalIgnoreCase);
+    }
+
+    private static async Task<PublicShellActivationResult?> TryActivateExistingHostWithStatusAsync(
+        LanMountainDesktopIpcClient ipcClient,
+        TimeSpan timeout)
+    {
+        try
+        {
+            var connected = ipcClient.IsConnected ||
+                            await TryConnectToPublicIpcAsync(ipcClient, timeout).ConfigureAwait(false);
+            if (!connected)
+            {
+                return null;
+            }
+
+            var shellProxy = ipcClient.CreateProxy<IPublicShellControlService>();
+            return await shellProxy.ActivateMainWindowWithStatusAsync().ConfigureAwait(false);
+        }
+        catch (Exception ex)
+        {
+            Logger.Warn($"Existing host activation probe failed: {ex.Message}");
+            return null;
+        }
+    }
+
+    private static async Task<PublicShellStatus?> TryGetPublicShellStatusAsync(
+        LanMountainDesktopIpcClient ipcClient)
+    {
+        try
+        {
+            var shellProxy = ipcClient.CreateProxy<IPublicShellControlService>();
+            return await shellProxy.GetShellStatusAsync().ConfigureAwait(false);
+        }
+        catch (Exception ex)
+        {
+            Logger.Warn($"Failed to query public shell status: {ex.Message}");
+            return null;
+        }
+    }
+
     private static async Task<StartupSuccessState?> TryRecoverWithPublicActivationAsync(
         LanMountainDesktopIpcClient ipcClient,
         Process hostProcess,
@@ -1000,6 +1418,100 @@ internal sealed class LauncherFlowCoordinator
         return null;
     }
 
+    private static LoadingStateMessage BuildDelayedLoadingState(
+        LoadingStateMessage loadingState,
+        string summaryMessage,
+        string detailMessage,
+        DateTimeOffset startedAtUtc)
+    {
+        var delayedItems = loadingState.ActiveItems
+            .Where(item => !string.Equals(item.Id, "launcher-soft-timeout", StringComparison.OrdinalIgnoreCase))
+            .ToList();
+
+        delayedItems.Insert(0, new LoadingItem
+        {
+            Id = "launcher-soft-timeout",
+            Type = LoadingItemType.System,
+            Name = "Startup still in progress",
+            Description = detailMessage,
+            State = LoadingState.Delayed,
+            ProgressPercent = Math.Max(loadingState.OverallProgressPercent, 1),
+            Message = detailMessage,
+            StartTime = startedAtUtc
+        });
+
+        return loadingState with
+        {
+            ActiveItems = delayedItems,
+            Message = summaryMessage,
+            Timestamp = DateTimeOffset.UtcNow,
+            TotalCount = Math.Max(loadingState.TotalCount, delayedItems.Count)
+        };
+    }
+
+    private static Dictionary<string, string> BuildAttemptDetails(
+        StartupAttemptRecord? trackedAttempt,
+        bool attachedToExistingAttempt,
+        bool ipcConnected,
+        bool hostProcessAlive,
+        StartupStage lastStage,
+        string lastStageMessage,
+        string? activationFailureReason,
+        bool softTimeoutShown,
+        bool recoveryActivationAttempted)
+    {
+        var details = new Dictionary<string, string>(StringComparer.OrdinalIgnoreCase)
+        {
+            ["hostProcessAlive"] = hostProcessAlive.ToString(),
+            ["attachedToExistingAttempt"] = attachedToExistingAttempt.ToString(),
+            ["ipcConnected"] = ipcConnected.ToString(),
+            ["ipcStage"] = lastStage.ToString(),
+            ["ipcMessage"] = lastStageMessage,
+            ["activationFailureReason"] = activationFailureReason ?? string.Empty,
+            ["softTimeoutShown"] = softTimeoutShown.ToString(),
+            ["recoveryActivationAttempted"] = recoveryActivationAttempted.ToString()
+        };
+
+        if (trackedAttempt is not null)
+        {
+            details["startupAttemptId"] = trackedAttempt.AttemptId;
+            details["startupAttemptState"] = trackedAttempt.State.ToString();
+            details["startupAttemptStartedAtUtc"] = trackedAttempt.StartedAtUtc.ToString("O");
+            details["startupAttemptUpdatedAtUtc"] = trackedAttempt.UpdatedAtUtc.ToString("O");
+            details["startupAttemptHeartbeatAtUtc"] = trackedAttempt.HeartbeatAtUtc.ToString("O");
+            details["successPolicy"] = trackedAttempt.SuccessPolicy;
+            details["hostPid"] = trackedAttempt.HostPid.ToString();
+            details["coordinatorPid"] = trackedAttempt.CoordinatorPid.ToString();
+            details["coordinatorPipeName"] = trackedAttempt.CoordinatorPipeName;
+            details["reservedBeforeHostStart"] = trackedAttempt.ReservedBeforeHostStart.ToString();
+            details["publicIpcConnected"] = trackedAttempt.PublicIpcConnected.ToString();
+            details["shellStatus"] = trackedAttempt.ShellStatus;
+        }
+
+        return details;
+    }
+
+    private static bool TryGetLiveProcess(int processId, out Process? process)
+    {
+        process = null;
+        if (processId <= 0)
+        {
+            return false;
+        }
+
+        try
+        {
+            process = Process.GetProcessById(processId);
+            return !process.HasExited;
+        }
+        catch
+        {
+            process?.Dispose();
+            process = null;
+            return false;
+        }
+    }
+
     private enum HostStartMode
     {
         ShellExecute,
@@ -1048,6 +1560,8 @@ internal sealed class LauncherFlowCoordinator
         private bool _trayReady;
         private bool _backgroundReady;
 
+        public string PolicyKey => _policy.ToString();
+
         public StartupSuccessTracker(CommandContext context)
         {
             var restartPresentation = LauncherRuntimeMetadata.GetRestartPresentationMode(context.RawArgs);

LanMountainDesktop.Launcher/Services/StartupAttemptRegistry.cs

@@ -0,0 +1,515 @@
+using System.Diagnostics;
+using System.Security.Cryptography;
+using System.Text;
+using System.Text.Json;
+using LanMountainDesktop.Launcher.Models;
+using LanMountainDesktop.Shared.Contracts.Launcher;
+
+namespace LanMountainDesktop.Launcher.Services;
+
+internal sealed class StartupAttemptRegistry
+{
+    private static readonly TimeSpan CoordinatorHeartbeatTimeout = TimeSpan.FromSeconds(10);
+    private static readonly JsonSerializerOptions SerializerOptions = new()
+    {
+        WriteIndented = true
+    };
+
+    private readonly string _statePath;
+    private readonly string _mutexName;
+    private string? _ownedAttemptId;
+
+    public StartupAttemptRegistry()
+        : this(Path.Combine(
+            Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData),
+            "LanMountainDesktop",
+            ".launcher",
+            "state",
+            "startup-attempt.json"))
+    {
+    }
+
+    internal StartupAttemptRegistry(string statePath)
+    {
+        _statePath = statePath;
+        _mutexName = $"LanMountainDesktop.Launcher.StartupAttempt.{ComputePathHash(statePath)}";
+    }
+
+    public StartupAttemptRecord StartOwnedAttempt(
+        int hostPid,
+        string launchSource,
+        string successPolicy,
+        StartupStage stage,
+        string? message)
+    {
+        var record = new StartupAttemptRecord
+        {
+            AttemptId = Guid.NewGuid().ToString("N"),
+            HostPid = hostPid,
+            CoordinatorPid = Environment.ProcessId,
+            LaunchSource = launchSource,
+            SuccessPolicy = successPolicy,
+            LastObservedStage = stage,
+            LastObservedMessage = message ?? string.Empty,
+            StartedAtUtc = DateTimeOffset.UtcNow,
+            UpdatedAtUtc = DateTimeOffset.UtcNow,
+            HeartbeatAtUtc = DateTimeOffset.UtcNow,
+            State = StartupAttemptState.Pending
+        };
+
+        ExecuteWithLock(() =>
+        {
+            SaveUnsafe(record);
+            _ownedAttemptId = record.AttemptId;
+        });
+
+        return Clone(record);
+    }
+
+    public bool TryReserveCoordinator(
+        string launchSource,
+        string successPolicy,
+        string coordinatorPipeName,
+        out StartupAttemptRecord reservedAttempt,
+        out StartupAttemptRecord? activeCoordinatorAttempt)
+    {
+        StartupAttemptRecord? reserved = null;
+        StartupAttemptRecord? active = null;
+
+        ExecuteWithLock(() =>
+        {
+            var existing = LoadUnsafe();
+            if (existing is not null && IsCoordinatorLive(existing))
+            {
+                active = Clone(existing);
+                return;
+            }
+
+            if (existing is not null && IsRecoverableCoordinatorAttempt(existing))
+            {
+                existing.CoordinatorPid = Environment.ProcessId;
+                existing.CoordinatorPipeName = coordinatorPipeName;
+                existing.HeartbeatAtUtc = DateTimeOffset.UtcNow;
+                existing.UpdatedAtUtc = DateTimeOffset.UtcNow;
+                if (existing.HostPid <= 0)
+                {
+                    existing.ReservedBeforeHostStart = true;
+                }
+
+                if (existing.State == StartupAttemptState.DetachedWaiting)
+                {
+                    existing.State = StartupAttemptState.SoftTimeout;
+                }
+
+                _ownedAttemptId = existing.AttemptId;
+                SaveUnsafe(existing);
+                reserved = Clone(existing);
+                return;
+            }
+
+            var now = DateTimeOffset.UtcNow;
+            var record = new StartupAttemptRecord
+            {
+                AttemptId = Guid.NewGuid().ToString("N"),
+                HostPid = 0,
+                CoordinatorPid = Environment.ProcessId,
+                CoordinatorPipeName = coordinatorPipeName,
+                LaunchSource = launchSource,
+                SuccessPolicy = successPolicy,
+                LastObservedStage = StartupStage.Initializing,
+                LastObservedMessage = "Launcher coordinator reserved startup ownership.",
+                StartedAtUtc = now,
+                UpdatedAtUtc = now,
+                HeartbeatAtUtc = now,
+                ReservedBeforeHostStart = true,
+                State = StartupAttemptState.Pending
+            };
+
+            _ownedAttemptId = record.AttemptId;
+            SaveUnsafe(record);
+            reserved = Clone(record);
+        });
+
+        reservedAttempt = reserved ?? new StartupAttemptRecord();
+        activeCoordinatorAttempt = active;
+        return reserved is not null;
+    }
+
+    public StartupAttemptRecord? GetOwnedAttempt()
+    {
+        StartupAttemptRecord? result = null;
+        if (string.IsNullOrWhiteSpace(_ownedAttemptId))
+        {
+            return null;
+        }
+
+        ExecuteWithLock(() =>
+        {
+            var record = LoadUnsafe();
+            if (record is not null && string.Equals(record.AttemptId, _ownedAttemptId, StringComparison.Ordinal))
+            {
+                result = Clone(record);
+            }
+        });
+
+        return result;
+    }
+
+    public StartupAttemptRecord? TryGetLiveCoordinatorAttempt()
+    {
+        StartupAttemptRecord? result = null;
+        ExecuteWithLock(() =>
+        {
+            var record = LoadUnsafe();
+            if (record is not null && IsCoordinatorLive(record))
+            {
+                result = Clone(record);
+            }
+        });
+
+        return result;
+    }
+
+    public StartupAttemptRecord? TryGetLatestAttempt()
+    {
+        StartupAttemptRecord? result = null;
+        ExecuteWithLock(() =>
+        {
+            var record = LoadUnsafe();
+            if (record is not null)
+            {
+                result = Clone(record);
+            }
+        });
+
+        return result;
+    }
+
+    public StartupAttemptRecord AssignOwnedHostProcess(
+        int hostPid,
+        StartupStage stage,
+        string? message)
+    {
+        StartupAttemptRecord? result = null;
+        UpdateOwned(record =>
+        {
+            record.HostPid = hostPid;
+            record.LastObservedStage = stage;
+            record.LastObservedMessage = message ?? record.LastObservedMessage;
+            record.ReservedBeforeHostStart = false;
+            result = Clone(record);
+        });
+
+        return result ?? StartOwnedAttempt(
+            hostPid,
+            string.Empty,
+            string.Empty,
+            stage,
+            message);
+    }
+
+    public bool AdoptAttempt(string attemptId)
+    {
+        if (string.IsNullOrWhiteSpace(attemptId))
+        {
+            return false;
+        }
+
+        var adopted = false;
+        ExecuteWithLock(() =>
+        {
+            var record = LoadUnsafe();
+            if (record is null || !string.Equals(record.AttemptId, attemptId, StringComparison.Ordinal))
+            {
+                return;
+            }
+
+            if (!IsAttachable(record))
+            {
+                return;
+            }
+
+            _ownedAttemptId = record.AttemptId;
+            if (record.State == StartupAttemptState.DetachedWaiting)
+            {
+                record.State = StartupAttemptState.SoftTimeout;
+            }
+
+            record.UpdatedAtUtc = DateTimeOffset.UtcNow;
+            SaveUnsafe(record);
+            adopted = true;
+        });
+
+        return adopted;
+    }
+
+    public StartupAttemptRecord? TryGetAttachableAttempt(string launchSource, string successPolicy)
+    {
+        StartupAttemptRecord? result = null;
+        ExecuteWithLock(() =>
+        {
+            var record = LoadUnsafe();
+            if (record is null ||
+                !IsAttachable(record) ||
+                !string.Equals(record.LaunchSource, launchSource, StringComparison.OrdinalIgnoreCase) ||
+                !string.Equals(record.SuccessPolicy, successPolicy, StringComparison.OrdinalIgnoreCase))
+            {
+                return;
+            }
+
+            result = Clone(record);
+        });
+
+        return result;
+    }
+
+    public void MarkOwnedIpcConnected()
+    {
+        UpdateOwned(record =>
+        {
+            record.IpcConnected = true;
+            record.PublicIpcConnected = true;
+        });
+    }
+
+    public void UpdateOwnedStage(StartupStage stage, string? message, bool ipcConnected)
+    {
+        UpdateOwned(record =>
+        {
+            record.LastObservedStage = stage;
+            record.LastObservedMessage = message ?? string.Empty;
+            if (ipcConnected)
+            {
+                record.IpcConnected = true;
+                record.PublicIpcConnected = true;
+            }
+        });
+    }
+
+    public void UpdateOwnedCoordinatorHeartbeat(LauncherCoordinatorStatus status)
+    {
+        UpdateOwned(record =>
+        {
+            record.CoordinatorPid = Environment.ProcessId;
+            record.HeartbeatAtUtc = DateTimeOffset.UtcNow;
+            record.LastObservedStage = status.LastObservedStage;
+            record.LastObservedMessage = status.LastObservedMessage;
+            record.IpcConnected = status.PublicIpcConnected;
+            record.PublicIpcConnected = status.PublicIpcConnected;
+            record.ShellStatus = status.ShellStatus?.ShellState ?? status.State;
+        });
+    }
+
+    public void MarkOwnedSoftTimeout(string? message)
+    {
+        UpdateOwned(record =>
+        {
+            record.State = StartupAttemptState.SoftTimeout;
+            record.LastObservedMessage = message ?? record.LastObservedMessage;
+        });
+    }
+
+    public void MarkOwnedDetachedWaiting()
+    {
+        UpdateOwned(record =>
+        {
+            if (record.State is StartupAttemptState.Pending or StartupAttemptState.SoftTimeout)
+            {
+                record.State = StartupAttemptState.DetachedWaiting;
+            }
+        });
+    }
+
+    public void MarkOwnedSucceeded(StartupStage stage, string? message)
+    {
+        UpdateOwned(record =>
+        {
+            record.State = StartupAttemptState.Succeeded;
+            record.LastObservedStage = stage;
+            record.LastObservedMessage = message ?? record.LastObservedMessage;
+        });
+    }
+
+    public void MarkOwnedFailed(StartupStage stage, string? message)
+    {
+        UpdateOwned(record =>
+        {
+            record.State = StartupAttemptState.Failed;
+            record.LastObservedStage = stage;
+            record.LastObservedMessage = message ?? record.LastObservedMessage;
+        });
+    }
+
+    private void UpdateOwned(Action<StartupAttemptRecord> update)
+    {
+        if (string.IsNullOrWhiteSpace(_ownedAttemptId))
+        {
+            return;
+        }
+
+        ExecuteWithLock(() =>
+        {
+            var record = LoadUnsafe();
+            if (record is null || !string.Equals(record.AttemptId, _ownedAttemptId, StringComparison.Ordinal))
+            {
+                return;
+            }
+
+            update(record);
+            record.UpdatedAtUtc = DateTimeOffset.UtcNow;
+            SaveUnsafe(record);
+        });
+    }
+
+    private void ExecuteWithLock(Action action)
+    {
+        using var mutex = new Mutex(false, _mutexName);
+        var hasHandle = false;
+        try
+        {
+            try
+            {
+                hasHandle = mutex.WaitOne(TimeSpan.FromSeconds(2));
+            }
+            catch (AbandonedMutexException)
+            {
+                hasHandle = true;
+            }
+
+            if (!hasHandle)
+            {
+                return;
+            }
+
+            action();
+        }
+        finally
+        {
+            if (hasHandle)
+            {
+                mutex.ReleaseMutex();
+            }
+        }
+    }
+
+    private StartupAttemptRecord? LoadUnsafe()
+    {
+        if (!File.Exists(_statePath))
+        {
+            return null;
+        }
+
+        try
+        {
+            var json = File.ReadAllText(_statePath);
+            return JsonSerializer.Deserialize<StartupAttemptRecord>(json, SerializerOptions);
+        }
+        catch
+        {
+            return null;
+        }
+    }
+
+    private void SaveUnsafe(StartupAttemptRecord record)
+    {
+        var directory = Path.GetDirectoryName(_statePath);
+        if (!string.IsNullOrWhiteSpace(directory))
+        {
+            Directory.CreateDirectory(directory);
+        }
+
+        File.WriteAllText(_statePath, JsonSerializer.Serialize(record, SerializerOptions));
+    }
+
+    private static bool IsAttachable(StartupAttemptRecord record)
+    {
+        if (record.State is not (StartupAttemptState.Pending or StartupAttemptState.SoftTimeout or StartupAttemptState.DetachedWaiting))
+        {
+            return false;
+        }
+
+        return TryGetLiveProcess(record.HostPid, out _);
+    }
+
+    private static bool IsRecoverableCoordinatorAttempt(StartupAttemptRecord record)
+    {
+        if (record.State is not (StartupAttemptState.Pending or StartupAttemptState.SoftTimeout or StartupAttemptState.DetachedWaiting))
+        {
+            return false;
+        }
+
+        if (record.HostPid <= 0)
+        {
+            return true;
+        }
+
+        return TryGetLiveProcess(record.HostPid, out _);
+    }
+
+    private static bool IsCoordinatorLive(StartupAttemptRecord record)
+    {
+        if (record.State is not (StartupAttemptState.Pending or StartupAttemptState.SoftTimeout or StartupAttemptState.DetachedWaiting))
+        {
+            return false;
+        }
+
+        if (record.CoordinatorPid <= 0 ||
+            string.IsNullOrWhiteSpace(record.CoordinatorPipeName) ||
+            DateTimeOffset.UtcNow - record.HeartbeatAtUtc > CoordinatorHeartbeatTimeout)
+        {
+            return false;
+        }
+
+        return TryGetLiveProcess(record.CoordinatorPid, out _);
+    }
+
+    private static bool TryGetLiveProcess(int processId, out Process? process)
+    {
+        process = null;
+        if (processId <= 0)
+        {
+            return false;
+        }
+
+        try
+        {
+            process = Process.GetProcessById(processId);
+            return !process.HasExited;
+        }
+        catch
+        {
+            process?.Dispose();
+            process = null;
+            return false;
+        }
+    }
+
+    private static string ComputePathHash(string statePath)
+    {
+        var bytes = SHA256.HashData(Encoding.UTF8.GetBytes(statePath.ToLowerInvariant()));
+        return Convert.ToHexString(bytes[..8]);
+    }
+
+    private static StartupAttemptRecord Clone(StartupAttemptRecord record)
+    {
+        return new StartupAttemptRecord
+        {
+            AttemptId = record.AttemptId,
+            HostPid = record.HostPid,
+            CoordinatorPid = record.CoordinatorPid,
+            CoordinatorPipeName = record.CoordinatorPipeName,
+            StartedAtUtc = record.StartedAtUtc,
+            UpdatedAtUtc = record.UpdatedAtUtc,
+            HeartbeatAtUtc = record.HeartbeatAtUtc,
+            LaunchSource = record.LaunchSource,
+            SuccessPolicy = record.SuccessPolicy,
+            LastObservedStage = record.LastObservedStage,
+            LastObservedMessage = record.LastObservedMessage,
+            IpcConnected = record.IpcConnected,
+            PublicIpcConnected = record.PublicIpcConnected,
+            ShellStatus = record.ShellStatus,
+            ReservedBeforeHostStart = record.ReservedBeforeHostStart,
+            State = record.State
+        };
+    }
+}

LanMountainDesktop.Launcher/Views/ErrorWindow.axaml

@@ -3,102 +3,96 @@
         xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
         xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
         xmlns:views="clr-namespace:LanMountainDesktop.Launcher.Views"
-        xmlns:ui="using:FluentAvalonia.UI.Controls"
         mc:Ignorable="d"
-        d:DesignWidth="520"
-        d:DesignHeight="280"
         x:Class="LanMountainDesktop.Launcher.Views.ErrorWindow"
         x:DataType="views:ErrorWindow"
-        Title="阑山桌面"
-        Width="520"
-        Height="280"
+        Title="LanMountain Desktop"
+        Width="560"
+        Height="320"
         CanResize="False"
         WindowStartupLocation="CenterScreen"
-        Background="{DynamicResource SolidBackgroundFillColorBaseBrush}"
+        Background="#111318"
         TransparencyLevelHint="None"
         Icon="/Assets/logo.ico">
   <Design.DataContext>
     <views:ErrorWindow />
   </Design.DataContext>
 
-  <!-- Fluent Design 风格对话框布局 -->
   <Grid RowDefinitions="*,Auto">
-    <!-- 主内容区域：左侧图标 + 右侧文字 -->
-    <Grid Grid.Row="0" Margin="24,24,24,16" ColumnDefinitions="Auto,*">
-      
-      <!-- 左侧：错误图标（可点击进入调试模式） -->
+    <Grid Grid.Row="0"
+          Margin="24"
+          ColumnDefinitions="Auto,*">
       <Border x:Name="ErrorIconBorder"
               Grid.Column="0"
-              Width="48"
-              Height="48"
-              Margin="0,4,16,0"
-              Background="{DynamicResource SystemFillColorCriticalBackgroundBrush}"
-              CornerRadius="24"
+              Width="52"
+              Height="52"
+              Margin="0,4,18,0"
+              Background="#2B161A"
+              CornerRadius="26"
               VerticalAlignment="Top">
-        <TextBlock Text="&#xEA39;"
+        <TextBlock Text="!"
                    FontSize="24"
-                   FontFamily="{DynamicResource SymbolThemeFontFamily}"
-                   Foreground="{DynamicResource SystemFillColorCriticalBrush}"
+                   FontWeight="Bold"
+                   Foreground="#FFB4AB"
                    HorizontalAlignment="Center"
-                   VerticalAlignment="Center"/>
+                   VerticalAlignment="Center" />
       </Border>
-      
-      <!-- 右侧：标题 + 内容 -->
-      <StackPanel Grid.Column="1" Spacing="8">
-        <!-- 标题 -->
+
+      <StackPanel Grid.Column="1"
+                  Spacing="10">
         <TextBlock x:Name="TitleText"
-                   Text="启动失败"
-                   FontSize="18"
+                   Text="Launcher could not confirm startup"
+                   FontSize="20"
                    FontWeight="SemiBold"
-                   Foreground="{DynamicResource TextFillColorPrimaryBrush}"
-                   TextWrapping="Wrap"/>
-        
-        <!-- 错误信息 -->
+                   Foreground="#F6F7FB"
+                   TextWrapping="Wrap" />
+
         <TextBlock x:Name="ErrorMessageText"
-                   Text="找不到阑山桌面应用程序。"
+                   Text="LanMountain Desktop did not reach the expected startup state."
                    FontSize="14"
-                   Foreground="{DynamicResource TextFillColorSecondaryBrush}"
+                   Foreground="#D2D7E1"
                    TextWrapping="Wrap"
-                   LineHeight="20"/>
-        
-        <!-- 建议信息 -->
+                   LineHeight="22" />
+
         <TextBlock x:Name="SuggestionText"
-                   Text="请确保应用程序已正确安装，或尝试重新安装。"
+                   Text="You can inspect logs, retry when the old process is gone, or reactivate the current instance."
                    FontSize="13"
-                   Foreground="{DynamicResource TextFillColorTertiaryBrush}"
+                   Foreground="#9BA5B7"
                    TextWrapping="Wrap"
-                   LineHeight="18"
-                   Margin="0,4,0,0"/>
+                   LineHeight="20" />
       </StackPanel>
     </Grid>
 
-    <!-- 底部：按钮区域 -->
     <Border Grid.Row="1"
-            Background="{DynamicResource CardBackgroundFillColorDefaultBrush}"
-            Padding="24,16">
-      <Grid ColumnDefinitions="*,Auto">
+            Padding="24,16"
+            Background="#171A21">
+      <Grid ColumnDefinitions="*,Auto,Auto,Auto"
+            ColumnSpacing="8">
         <Button x:Name="OpenLogButton"
                 Grid.Column="0"
-                Content="打开日志"
-                Width="100"
-                Height="32"
-                FontSize="13"
-                HorizontalAlignment="Left"/>
-        <StackPanel Grid.Column="1"
-                    Orientation="Horizontal" 
-                    Spacing="8">
-          <Button x:Name="ExitButton"
-                  Content="退出"
-                  Width="80"
-                  Height="32"
-                  FontSize="13"/>
-          <Button x:Name="RetryButton"
-                  Content="重试"
-                  Width="80"
-                  Height="32"
-                  FontSize="13"
-                  Theme="{DynamicResource AccentButtonTheme}"/>
-        </StackPanel>
+                Content="Open Logs"
+                MinWidth="108"
+                Height="34"
+                HorizontalAlignment="Left" />
+
+        <Button x:Name="SecondaryActionButton"
+                Grid.Column="1"
+                Content="Wait"
+                MinWidth="108"
+                Height="34"
+                IsVisible="False" />
+
+        <Button x:Name="ExitButton"
+                Grid.Column="2"
+                Content="Exit"
+                MinWidth="90"
+                Height="34" />
+
+        <Button x:Name="PrimaryActionButton"
+                Grid.Column="3"
+                Content="Retry"
+                MinWidth="108"
+                Height="34" />
       </Grid>
     </Border>
   </Grid>

LanMountainDesktop.Launcher/Views/ErrorWindow.axaml.cs

@@ -1,542 +1,365 @@
+using System.Diagnostics;
 using Avalonia.Controls;
+using Avalonia.Input;
 using Avalonia.Interactivity;
 using Avalonia.Markup.Xaml;
-using Avalonia.Platform.Storage;
 using LanMountainDesktop.Launcher.Services;
-using System.Diagnostics;
 
 namespace LanMountainDesktop.Launcher.Views;
 
-/// <summary>
-/// 错误窗口 - 显示启动失败信息，支持调试模式（隐藏入口）
-/// </summary>
 public partial class ErrorWindow : Window
 {
-    private readonly TaskCompletionSource<ErrorWindowResult> _completionSource = new();
-    private int _iconClickCount = 0;
     private const int DebugModeClickThreshold = 5;
-    private bool _isDebugMode = false;
-    private string? _customHostPath;
+
+    private readonly TaskCompletionSource<ErrorWindowResult> _completionSource = new(TaskCreationOptions.RunContinuationsAsynchronously);
+    private int _iconClickCount;
+    private bool _isDebugMode;
     private bool _devModeEnabled;
+    private string? _customHostPath;
+    private ErrorWindowResult _primaryAction = ErrorWindowResult.Retry;
+    private ErrorWindowResult? _secondaryAction;
 
     public ErrorWindow()
     {
         AvaloniaXamlLoader.Load(this);
 
-        // 先加载保存的状态
         _devModeEnabled = LoadDevModeStateInternal();
         _customHostPath = LoadCustomHostPathInternal();
 
-        // 延迟到窗口加载完成后再初始化组件，确保视觉树已准备好
-        this.Loaded += OnWindowLoaded;
-        this.Opened += OnWindowOpened;
+        Loaded += OnWindowLoaded;
+        Closed += (_, _) => _completionSource.TrySetResult(ErrorWindowResult.Exit);
+        ConfigureForGenericFailure(allowRetry: true);
     }
 
-    /// <summary>
-    /// 窗口加载完成事件 - 视觉树已准备好
-    /// </summary>
-    private void OnWindowLoaded(object? sender, RoutedEventArgs e)
-    {
-        Console.WriteLine("[ErrorWindow] Window loaded, initializing components...");
-        InitializeComponents();
-    }
-
-    /// <summary>
-    /// 窗口打开事件
-    /// </summary>
-    private void OnWindowOpened(object? sender, EventArgs e)
-    {
-        Console.WriteLine("[ErrorWindow] Window opened and visible");
-    }
-
-    private void InitializeComponents()
-    {
-        Console.WriteLine("[ErrorWindow] Initializing components...");
-        
-        // 错误图标点击事件（进入调试模式 - 隐藏功能）
-        var errorIconBorder = this.FindControl<Border>("ErrorIconBorder");
-        if (errorIconBorder is not null)
-        {
-            errorIconBorder.PointerPressed += OnErrorIconClick;
-            Console.WriteLine("[ErrorWindow] ErrorIconBorder event bound successfully");
-        }
-        else
-        {
-            Console.Error.WriteLine("[ErrorWindow] Failed to find ErrorIconBorder!");
-        }
-
-        // 按钮事件
-        var retryButton = this.FindControl<Button>("RetryButton");
-        var exitButton = this.FindControl<Button>("ExitButton");
-        var openLogButton = this.FindControl<Button>("OpenLogButton");
-
-        if (retryButton is not null)
-        {
-            retryButton.Click += OnRetryClick;
-            Console.WriteLine("[ErrorWindow] RetryButton event bound");
-        }
-        else
-        {
-            Console.Error.WriteLine("[ErrorWindow] Failed to find RetryButton!");
-        }
-
-        if (exitButton is not null)
-        {
-            exitButton.Click += OnExitClick;
-            Console.WriteLine("[ErrorWindow] ExitButton event bound");
-        }
-        else
-        {
-            Console.Error.WriteLine("[ErrorWindow] Failed to find ExitButton!");
-        }
-
-        if (openLogButton is not null)
-        {
-            openLogButton.Click += OnOpenLogClick;
-            Console.WriteLine("[ErrorWindow] OpenLogButton event bound");
-        }
-        else
-        {
-            Console.Error.WriteLine("[ErrorWindow] Failed to find OpenLogButton!");
-        }
-        
-        Console.WriteLine("[ErrorWindow] Components initialization completed");
-    }
-
-    /// <summary>
-    /// 设置错误消息
-    /// </summary>
     public void SetErrorMessage(string message)
     {
-        var errorText = this.FindControl<TextBlock>("ErrorMessageText");
-        if (errorText is not null)
+        if (this.FindControl<TextBlock>("ErrorMessageText") is { } errorText)
         {
             errorText.Text = message;
         }
     }
 
-    /// <summary>
-    /// 设置调试模式
-    /// </summary>
     public void SetDebugMode(bool isDebugMode)
     {
         _isDebugMode = isDebugMode;
-        var titleText = this.FindControl<TextBlock>("TitleText");
-        if (titleText is not null && isDebugMode)
+        if (isDebugMode && this.FindControl<TextBlock>("TitleText") is { } titleText)
         {
-            titleText.Text = "[调试模式] 错误页面";
+            titleText.Text = "[Debug] Launcher error";
         }
     }
 
-    /// <summary>
-    /// 获取用户选择的主程序路径
-    /// </summary>
-    public string? GetCustomHostPath() => _customHostPath;
-
-    /// <summary>
-    /// 是否启用了开发模式
-    /// </summary>
-    public bool IsDevModeEnabled() => _devModeEnabled;
-
-    /// <summary>
-    /// 等待用户选择
-    /// </summary>
-    public Task<ErrorWindowResult> WaitForChoiceAsync()
+    public void ConfigureForHostNotFound()
     {
-        return _completionSource.Task;
+        ApplyActionLayout(
+            title: "Launcher could not find the desktop executable",
+            suggestion: "Pick another executable in debug mode, inspect logs, or retry after fixing the deployment path.",
+            primaryLabel: "Retry",
+            primaryAction: ErrorWindowResult.Retry,
+            secondaryLabel: null,
+            secondaryAction: null);
     }
 
-    /// <summary>
-    /// 错误图标点击事件 - 连续点击 5 次进入调试模式（隐藏功能）
-    /// </summary>
-    private void OnErrorIconClick(object? sender, Avalonia.Input.PointerPressedEventArgs e)
+    public void ConfigureForGenericFailure(bool allowRetry)
+    {
+        ApplyActionLayout(
+            title: "Launcher could not confirm startup",
+            suggestion: allowRetry
+                ? "Inspect logs, then retry once the previous startup attempt has fully finished."
+                : "Inspect logs or exit. Launcher will avoid creating another desktop process while the old one is still running.",
+            primaryLabel: allowRetry ? "Retry" : "Activate",
+            primaryAction: allowRetry ? ErrorWindowResult.Retry : ErrorWindowResult.ActivateExisting,
+            secondaryLabel: allowRetry ? null : "Wait",
+            secondaryAction: allowRetry ? null : ErrorWindowResult.ContinueWaiting);
+    }
+
+    public void ConfigureForRunningHostFailure(int? hostPid)
+    {
+        var pidHint = hostPid is > 0 ? $" Current host PID: {hostPid}." : string.Empty;
+        ApplyActionLayout(
+            title: "Startup is still pending",
+            suggestion: $"The desktop process is still running, so Launcher will not start a second instance.{pidHint}",
+            primaryLabel: "Activate",
+            primaryAction: ErrorWindowResult.ActivateExisting,
+            secondaryLabel: "Wait",
+            secondaryAction: ErrorWindowResult.ContinueWaiting);
+    }
+
+    public string? GetCustomHostPath() => _customHostPath;
+
+    public bool IsDevModeEnabled() => _devModeEnabled;
+
+    public Task<ErrorWindowResult> WaitForChoiceAsync() => _completionSource.Task;
+
+    public static bool CheckDevModeEnabled() => LoadDevModeStateInternal();
+
+    public static string? GetSavedCustomHostPath() => LoadCustomHostPathInternal();
+
+    private void OnWindowLoaded(object? sender, RoutedEventArgs e)
+    {
+        if (this.FindControl<Border>("ErrorIconBorder") is { } errorIconBorder)
+        {
+            errorIconBorder.PointerPressed += OnErrorIconClick;
+        }
+
+        if (this.FindControl<Button>("PrimaryActionButton") is { } primaryActionButton)
+        {
+            primaryActionButton.Click += OnPrimaryActionClick;
+        }
+
+        if (this.FindControl<Button>("SecondaryActionButton") is { } secondaryActionButton)
+        {
+            secondaryActionButton.Click += OnSecondaryActionClick;
+        }
+
+        if (this.FindControl<Button>("ExitButton") is { } exitButton)
+        {
+            exitButton.Click += (_, _) => _completionSource.TrySetResult(ErrorWindowResult.Exit);
+        }
+
+        if (this.FindControl<Button>("OpenLogButton") is { } openLogButton)
+        {
+            openLogButton.Click += OnOpenLogClick;
+        }
+    }
+
+    private void ApplyActionLayout(
+        string title,
+        string suggestion,
+        string primaryLabel,
+        ErrorWindowResult primaryAction,
+        string? secondaryLabel,
+        ErrorWindowResult? secondaryAction)
+    {
+        _primaryAction = primaryAction;
+        _secondaryAction = secondaryAction;
+
+        if (this.FindControl<TextBlock>("TitleText") is { } titleText && !_isDebugMode)
+        {
+            titleText.Text = title;
+        }
+
+        if (this.FindControl<TextBlock>("SuggestionText") is { } suggestionText)
+        {
+            suggestionText.Text = suggestion;
+        }
+
+        if (this.FindControl<Button>("PrimaryActionButton") is { } primaryButton)
+        {
+            primaryButton.Content = primaryLabel;
+        }
+
+        if (this.FindControl<Button>("SecondaryActionButton") is { } secondaryButton)
+        {
+            secondaryButton.IsVisible = !string.IsNullOrWhiteSpace(secondaryLabel);
+            secondaryButton.Content = secondaryLabel ?? string.Empty;
+        }
+    }
+
+    private void OnPrimaryActionClick(object? sender, RoutedEventArgs e)
+    {
+        _completionSource.TrySetResult(_primaryAction);
+    }
+
+    private void OnSecondaryActionClick(object? sender, RoutedEventArgs e)
+    {
+        _completionSource.TrySetResult(_secondaryAction ?? ErrorWindowResult.Exit);
+    }
+
+    private void OnErrorIconClick(object? sender, PointerPressedEventArgs e)
     {
         _iconClickCount++;
-
         if (_iconClickCount >= DebugModeClickThreshold && !_isDebugMode)
         {
             EnterDebugMode();
         }
     }
 
-    /// <summary>
-    /// 进入调试模式 - 显示调试窗口
-    /// </summary>
     private async void EnterDebugMode()
     {
         _isDebugMode = true;
 
-        // 创建并显示调试窗口
         var debugWindow = new ErrorDebugWindow(_devModeEnabled, _customHostPath)
         {
             WindowStartupLocation = WindowStartupLocation.CenterOwner
         };
 
-        // 订阅调试窗口关闭事件
-        debugWindow.Closed += (s, e) =>
+        debugWindow.Closed += (_, _) =>
         {
-            // 更新状态
             _devModeEnabled = debugWindow.IsDevModeEnabled;
             _customHostPath = debugWindow.SelectedHostPath;
-
-            // 保存开发模式状态和自定义路径
             SaveDevModeStateInternal(_devModeEnabled);
             SaveCustomHostPathInternal(_customHostPath);
 
-            // 如果启用了开发模式且没有选择路径，自动扫描
-            if (_devModeEnabled && string.IsNullOrEmpty(_customHostPath))
+            if (_devModeEnabled && string.IsNullOrWhiteSpace(_customHostPath))
             {
                 ScanDevPaths();
-                // 扫描到路径后也保存
-                if (!string.IsNullOrEmpty(_customHostPath))
-                {
-                    SaveCustomHostPathInternal(_customHostPath);
-                }
+                SaveCustomHostPathInternal(_customHostPath);
             }
+
+            _isDebugMode = false;
+            _iconClickCount = 0;
         };
 
         await debugWindow.ShowDialog(this);
     }
 
-    /// <summary>
-    /// 扫描开发路径
-    /// </summary>
-    private void ScanDevPaths()
-    {
-        var executable = OperatingSystem.IsWindows() ? "LanMountainDesktop.exe" : "LanMountainDesktop";
-        var possiblePaths = new[]
-        {
-            Path.Combine(AppContext.BaseDirectory, "..", "..", "LanMountainDesktop", "bin", "Debug", "net10.0", executable),
-            Path.Combine(AppContext.BaseDirectory, "..", "..", "LanMountainDesktop", "bin", "Release", "net10.0", executable),
-            Path.Combine(AppContext.BaseDirectory, "..", "LanMountainDesktop", "bin", "Debug", "net10.0", executable),
-            Path.Combine(AppContext.BaseDirectory, "..", "LanMountainDesktop", "bin", "Release", "net10.0", executable),
-            Path.Combine(AppContext.BaseDirectory, "..", "dev-test", "app-1.0.0-dev", executable),
-        };
-
-        foreach (var path in possiblePaths.Select(Path.GetFullPath).Distinct())
-        {
-            if (File.Exists(path))
-            {
-                _customHostPath = path;
-                break;
-            }
-        }
-    }
-
-    /// <summary>
-    /// 获取配置存储的基础目录
-    /// </summary>
-    private static string GetConfigBaseDirectory()
-    {
-        try
-        {
-            // 优先使用 LocalApplicationData（用户状态）
-            var appData = Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData);
-            if (!string.IsNullOrEmpty(appData))
-            {
-                var configDir = Path.Combine(appData, "LanMountainDesktop", ".launcher");
-                return configDir;
-            }
-        }
-        catch
-        {
-            // LocalApplicationData 不可用，回退到 Launcher 所在目录
-        }
-
-        // 回退方案：使用 Launcher 所在目录
-        try
-        {
-            var launcherDir = AppContext.BaseDirectory;
-            var configDir = Path.Combine(launcherDir, ".launcher");
-            return configDir;
-        }
-        catch
-        {
-            // 最后的兜底：使用当前目录
-            return Path.Combine(Directory.GetCurrentDirectory(), ".launcher");
-        }
-    }
-
-    /// <summary>
-    /// 确保配置目录存在
-    /// </summary>
-    private static bool EnsureConfigDirectory(string dirPath)
-    {
-        try
-        {
-            if (!Directory.Exists(dirPath))
-            {
-                Directory.CreateDirectory(dirPath);
-                Console.WriteLine($"[ErrorWindow] Created config directory: {dirPath}");
-            }
-            return true;
-        }
-        catch (Exception ex)
-        {
-            Console.Error.WriteLine($"[ErrorWindow] Failed to create config directory: {ex.Message}");
-            return false;
-        }
-    }
-
-    /// <summary>
-    /// 保存开发模式状态（内部方法）
-    /// </summary>
-    private static void SaveDevModeStateInternal(bool enabled)
-    {
-        try
-        {
-            var configDir = GetConfigBaseDirectory();
-            if (!EnsureConfigDirectory(configDir))
-            {
-                Console.Error.WriteLine("[ErrorWindow] Cannot save dev mode: config directory unavailable");
-                return;
-            }
-
-            var devModeFile = Path.Combine(configDir, "devmode.config");
-            File.WriteAllText(devModeFile, enabled ? "1" : "0");
-            Console.WriteLine($"[ErrorWindow] Dev mode state saved: {enabled}");
-        }
-        catch (Exception ex)
-        {
-            Console.Error.WriteLine($"[ErrorWindow] Failed to save dev mode state: {ex.Message}");
-        }
-    }
-
-    /// <summary>
-    /// 加载开发模式状态（内部方法）
-    /// </summary>
-    private static bool LoadDevModeStateInternal()
-    {
-        try
-        {
-            var configDir = GetConfigBaseDirectory();
-            var devModeFile = Path.Combine(configDir, "devmode.config");
-
-            if (File.Exists(devModeFile))
-            {
-                var content = File.ReadAllText(devModeFile).Trim();
-                var enabled = content == "1";
-                Console.WriteLine($"[ErrorWindow] Dev mode state loaded: {enabled}");
-                return enabled;
-            }
-        }
-        catch (Exception ex)
-        {
-            Console.Error.WriteLine($"[ErrorWindow] Failed to load dev mode state: {ex.Message}");
-        }
-        return false;
-    }
-
-    /// <summary>
-    /// 保存自定义主程序路径（内部方法）
-    /// </summary>
-    private static void SaveCustomHostPathInternal(string? path)
-    {
-        try
-        {
-            var configDir = GetConfigBaseDirectory();
-            if (!EnsureConfigDirectory(configDir))
-            {
-                Console.Error.WriteLine("[ErrorWindow] Cannot save custom path: config directory unavailable");
-                return;
-            }
-
-            var hostPathFile = Path.Combine(configDir, "custom-host-path.config");
-            File.WriteAllText(hostPathFile, path ?? string.Empty);
-            Console.WriteLine($"[ErrorWindow] Custom host path saved: {path}");
-        }
-        catch (Exception ex)
-        {
-            Console.Error.WriteLine($"[ErrorWindow] Failed to save custom host path: {ex.Message}");
-        }
-    }
-
-    /// <summary>
-    /// 加载自定义主程序路径（内部方法）
-    /// </summary>
-    private static string? LoadCustomHostPathInternal()
-    {
-        try
-        {
-            var configDir = GetConfigBaseDirectory();
-            var hostPathFile = Path.Combine(configDir, "custom-host-path.config");
-
-            if (File.Exists(hostPathFile))
-            {
-                var content = File.ReadAllText(hostPathFile).Trim();
-                // 验证路径是否仍然有效
-                if (!string.IsNullOrEmpty(content) && File.Exists(content))
-                {
-                    Console.WriteLine($"[ErrorWindow] Custom host path loaded: {content}");
-                    return content;
-                }
-
-                // 路径已失效，清理配置文件
-                if (!string.IsNullOrEmpty(content))
-                {
-                    Console.WriteLine($"[ErrorWindow] Custom host path is no longer valid: {content}");
-                    try
-                    {
-                        File.Delete(hostPathFile);
-                        Console.WriteLine("[ErrorWindow] Cleared invalid custom host path");
-                    }
-                    catch (Exception clearEx)
-                    {
-                        Console.Error.WriteLine($"[ErrorWindow] Failed to clear invalid host path: {clearEx.Message}");
-                    }
-                }
-            }
-        }
-        catch (Exception ex)
-        {
-            Console.Error.WriteLine($"[ErrorWindow] Failed to load custom host path: {ex.Message}");
-        }
-        return null;
-    }
-
-    /// <summary>
-    /// 检查是否启用了开发模式（静态方法，启动时调用）
-    /// </summary>
-    public static bool CheckDevModeEnabled()
-    {
-        return LoadDevModeStateInternal();
-    }
-
-    /// <summary>
-    /// 获取保存的自定义主程序路径（静态方法，启动时调用）
-    /// </summary>
-    public static string? GetSavedCustomHostPath()
-    {
-        return LoadCustomHostPathInternal();
-    }
-
-    private void OnRetryClick(object? sender, RoutedEventArgs e)
-    {
-        _completionSource.TrySetResult(ErrorWindowResult.Retry);
-    }
-
-    private void OnExitClick(object? sender, RoutedEventArgs e)
-    {
-        _completionSource.TrySetResult(ErrorWindowResult.Exit);
-    }
-
-    /// <summary>
-    /// 打开日志文件
-    /// </summary>
     private async void OnOpenLogClick(object? sender, RoutedEventArgs e)
     {
         try
         {
             var logFilePath = Logger.GetLogFilePath();
-
-            if (string.IsNullOrEmpty(logFilePath) || !File.Exists(logFilePath))
+            if (!string.IsNullOrWhiteSpace(logFilePath) && File.Exists(logFilePath))
             {
-                // 如果没有日志文件，打开日志目录
-                var logDir = Path.GetDirectoryName(logFilePath);
-                if (!string.IsNullOrEmpty(logDir) && Directory.Exists(logDir))
-                {
-                    OpenFolder(logDir);
-                }
-                else
-                {
-                    // 尝试打开配置目录
-                    var configDir = GetConfigBaseDirectory();
-                    if (Directory.Exists(configDir))
-                    {
-                        OpenFolder(configDir);
-                    }
-                    else
-                    {
-                        Console.WriteLine("[ErrorWindow] No log file or directory available");
-                    }
-                }
+                OpenPath(logFilePath);
                 return;
             }
 
-            Console.WriteLine($"[ErrorWindow] Opening log file: {logFilePath}");
-            OpenFile(logFilePath);
+            var logDirectory = !string.IsNullOrWhiteSpace(logFilePath)
+                ? Path.GetDirectoryName(logFilePath)
+                : null;
+            if (!string.IsNullOrWhiteSpace(logDirectory) && Directory.Exists(logDirectory))
+            {
+                OpenPath(logDirectory);
+                return;
+            }
+
+            var configDirectory = GetConfigBaseDirectory();
+            if (Directory.Exists(configDirectory))
+            {
+                OpenPath(configDirectory);
+            }
         }
         catch (Exception ex)
         {
-            Console.Error.WriteLine($"[ErrorWindow] Failed to open log: {ex.Message}");
+            Debug.WriteLine($"[ErrorWindow] Failed to open log path: {ex}");
+        }
+
+        await Task.CompletedTask;
+    }
+
+    private void ScanDevPaths()
+    {
+        var executable = OperatingSystem.IsWindows() ? "LanMountainDesktop.exe" : "LanMountainDesktop";
+        var candidatePaths = new[]
+        {
+            Path.Combine(AppContext.BaseDirectory, "..", "..", "LanMountainDesktop", "bin", "Debug", "net10.0", executable),
+            Path.Combine(AppContext.BaseDirectory, "..", "..", "LanMountainDesktop", "bin", "Release", "net10.0", executable),
+            Path.Combine(AppContext.BaseDirectory, "..", "LanMountainDesktop", "bin", "Debug", "net10.0", executable),
+            Path.Combine(AppContext.BaseDirectory, "..", "LanMountainDesktop", "bin", "Release", "net10.0", executable)
+        };
+
+        foreach (var candidate in candidatePaths.Select(Path.GetFullPath).Distinct())
+        {
+            if (File.Exists(candidate))
+            {
+                _customHostPath = candidate;
+                break;
+            }
         }
     }
 
-    /// <summary>
-    /// 打开文件
-    /// </summary>
-    private static void OpenFile(string filePath)
+    private static void OpenPath(string path)
     {
-        try
+        if (OperatingSystem.IsWindows())
         {
-            if (OperatingSystem.IsWindows())
+            Process.Start(new ProcessStartInfo
             {
-                Process.Start(new ProcessStartInfo
-                {
-                    FileName = "explorer.exe",
-                    Arguments = $"\"{filePath}\"",
-                    UseShellExecute = true
-                });
-            }
-            else if (OperatingSystem.IsMacOS())
-            {
-                Process.Start("open", filePath);
-            }
-            else if (OperatingSystem.IsLinux())
-            {
-                Process.Start("xdg-open", filePath);
-            }
+                FileName = "explorer.exe",
+                Arguments = $"\"{path}\"",
+                UseShellExecute = true
+            });
+            return;
         }
-        catch (Exception ex)
+
+        if (OperatingSystem.IsMacOS())
         {
-            Console.Error.WriteLine($"[ErrorWindow] Failed to open file: {ex.Message}");
+            Process.Start("open", path);
+            return;
+        }
+
+        if (OperatingSystem.IsLinux())
+        {
+            Process.Start("xdg-open", path);
         }
     }
 
-    /// <summary>
-    /// 打开文件夹
-    /// </summary>
-    private static void OpenFolder(string folderPath)
+    private static string GetConfigBaseDirectory()
+    {
+        var appData = Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData);
+        if (!string.IsNullOrWhiteSpace(appData))
+        {
+            return Path.Combine(appData, "LanMountainDesktop", ".launcher");
+        }
+
+        return Path.Combine(AppContext.BaseDirectory, ".launcher");
+    }
+
+    private static string GetDevModePath() => Path.Combine(GetConfigBaseDirectory(), "dev-mode.flag");
+
+    private static string GetCustomHostPathFile() => Path.Combine(GetConfigBaseDirectory(), "custom-host-path.txt");
+
+    private static bool LoadDevModeStateInternal()
     {
         try
         {
-            if (OperatingSystem.IsWindows())
-            {
-                Process.Start(new ProcessStartInfo
-                {
-                    FileName = "explorer.exe",
-                    Arguments = $"\"{folderPath}\"",
-                    UseShellExecute = true
-                });
-            }
-            else if (OperatingSystem.IsMacOS())
-            {
-                Process.Start("open", folderPath);
-            }
-            else if (OperatingSystem.IsLinux())
-            {
-                Process.Start("xdg-open", folderPath);
-            }
+            return File.Exists(GetDevModePath()) &&
+                   bool.TryParse(File.ReadAllText(GetDevModePath()).Trim(), out var enabled) &&
+                   enabled;
         }
-        catch (Exception ex)
+        catch
+        {
+            return false;
+        }
+    }
+
+    private static void SaveDevModeStateInternal(bool enabled)
+    {
+        try
+        {
+            Directory.CreateDirectory(GetConfigBaseDirectory());
+            File.WriteAllText(GetDevModePath(), enabled.ToString());
+        }
+        catch
+        {
+        }
+    }
+
+    private static string? LoadCustomHostPathInternal()
+    {
+        try
+        {
+            var pathFile = GetCustomHostPathFile();
+            if (!File.Exists(pathFile))
+            {
+                return null;
+            }
+
+            var savedPath = File.ReadAllText(pathFile).Trim();
+            return string.IsNullOrWhiteSpace(savedPath) ? null : savedPath;
+        }
+        catch
+        {
+            return null;
+        }
+    }
+
+    private static void SaveCustomHostPathInternal(string? customHostPath)
+    {
+        try
+        {
+            Directory.CreateDirectory(GetConfigBaseDirectory());
+            File.WriteAllText(GetCustomHostPathFile(), customHostPath ?? string.Empty);
+        }
+        catch
         {
-            Console.Error.WriteLine($"[ErrorWindow] Failed to open folder: {ex.Message}");
         }
     }
 }
 
-/// <summary>
-/// 错误窗口用户选择结果
-/// </summary>
 public enum ErrorWindowResult
 {
-    /// <summary>
-    /// 重试
-    /// </summary>
     Retry,
-
-    /// <summary>
-    /// 退出
-    /// </summary>
-    Exit
+    Exit,
+    ActivateExisting,
+    ContinueWaiting
 }

LanMountainDesktop.Launcher/Views/SplashWindow.axaml

@@ -3,85 +3,92 @@
         xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
         xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
         xmlns:views="clr-namespace:LanMountainDesktop.Launcher.Views"
-        xmlns:ui="using:FluentAvalonia.UI.Controls"
         mc:Ignorable="d"
-        d:DesignWidth="480"
-        d:DesignHeight="320"
         x:Class="LanMountainDesktop.Launcher.Views.SplashWindow"
         x:DataType="views:SplashWindow"
         Title="LanMountain Desktop"
         Width="480"
         Height="320"
         CanResize="False"
+        ShowInTaskbar="False"
         WindowStartupLocation="CenterScreen"
         SystemDecorations="None"
-        Background="{DynamicResource SolidBackgroundFillColorBaseBrush}"
+        Background="#0B0B0B"
         TransparencyLevelHint="None"
         Icon="/Assets/logo.ico">
   <Design.DataContext>
     <views:SplashWindow />
   </Design.DataContext>
 
-  <Grid>
-    <!-- 左上角：应用名称 -->
-    <TextBlock x:Name="AppNameText"
-               Text="LanMountain Desktop"
-               FontSize="24"
-               FontWeight="SemiBold"
-               VerticalAlignment="Top"
-               HorizontalAlignment="Left"
-               Margin="24,24,0,0"
-               Foreground="{DynamicResource TextFillColorPrimaryBrush}" />
-
-    <!-- 底部区域：进度条和状态 -->
-    <Grid VerticalAlignment="Bottom" Margin="24,0,24,24">
-      <Grid.RowDefinitions>
-        <RowDefinition Height="Auto"/>
-        <RowDefinition Height="Auto"/>
-      </Grid.RowDefinitions>
-      
-      <!-- 第一行：左下角版本信息，右下角阶段文字 -->
-      <Grid Grid.Row="0" Margin="0,0,0,8">
-        <Grid.ColumnDefinitions>
-          <ColumnDefinition Width="*"/>
-          <ColumnDefinition Width="Auto"/>
-        </Grid.ColumnDefinitions>
-        
-        <!-- 左下角：版本和开发代号 - 可点击打开开发者界面（隐藏功能） -->
-        <Border x:Name="VersionTextBorder"
-                Grid.Column="0"
-                Background="Transparent"
-                Cursor="Hand"
-                HorizontalAlignment="Left"
-                VerticalAlignment="Bottom">
-          <TextBlock x:Name="VersionText"
-                     FontSize="11"
-                     Foreground="{DynamicResource TextFillColorSecondaryBrush}"
-                     Opacity="0.8"
-                     Text="1.0.0 (Administrate)" />
-        </Border>
-        
-        <!-- 右下角：阶段文字 -->
-        <TextBlock x:Name="StatusText"
-                   Grid.Column="1"
-                   FontSize="11"
-                   Foreground="{DynamicResource TextFillColorSecondaryBrush}"
-                   HorizontalAlignment="Right"
-                   VerticalAlignment="Bottom"
-                   Opacity="0.8"
-                   Text="Initializing..." />
+  <Grid RowDefinitions="*,Auto"
+        Background="#0B0B0B">
+    <Grid Grid.Row="0">
+      <Grid x:Name="CompactHero"
+            Margin="24">
+        <TextBlock x:Name="AppNameText"
+                   Text="LanMountain Desktop"
+                   FontSize="24"
+                   FontWeight="SemiBold"
+                   VerticalAlignment="Top"
+                   HorizontalAlignment="Left"
+                   Foreground="#F6F7FB" />
+      </Grid>
+
+      <Grid x:Name="FullscreenHero"
+            IsVisible="False">
+        <StackPanel HorizontalAlignment="Center"
+                    VerticalAlignment="Center"
+                    Spacing="24">
+          <Border Width="240"
+                  Height="240"
+                  Background="Transparent">
+            <Image Source="/Assets/logo_nightly.png"
+                   Stretch="Uniform" />
+          </Border>
+
+          <TextBlock Text="LanMountain Desktop"
+                     HorizontalAlignment="Center"
+                     FontSize="26"
+                     FontWeight="SemiBold"
+                     Foreground="#F6F7FB" />
+        </StackPanel>
       </Grid>
-      
-      <!-- 底部：进度条 -->
-      <ProgressBar x:Name="ProgressIndicator"
-                   Grid.Row="1"
-                   Minimum="0"
-                   Maximum="100"
-                   Value="0"
-                   Height="4"
-                   IsIndeterminate="False"
-                   Foreground="{DynamicResource AccentFillColorDefaultBrush}"
-                   Background="{DynamicResource ControlStrokeColorDefaultBrush}" />
     </Grid>
+
+    <Border Grid.Row="1"
+            Padding="24,18,24,24"
+            Background="Transparent">
+      <Grid RowDefinitions="Auto,Auto"
+            RowSpacing="10">
+        <Grid ColumnDefinitions="*,Auto">
+          <Border x:Name="VersionTextBorder"
+                  Background="Transparent"
+                  Cursor="Hand"
+                  HorizontalAlignment="Left">
+            <TextBlock x:Name="VersionText"
+                       FontSize="11"
+                       Foreground="#B9C0CC"
+                       Text="0.0.0-dev (Administrate)" />
+          </Border>
+
+          <TextBlock x:Name="StatusText"
+                     Grid.Column="1"
+                     FontSize="11"
+                     Foreground="#B9C0CC"
+                     HorizontalAlignment="Right"
+                     Text="Initializing..." />
+        </Grid>
+
+        <ProgressBar x:Name="ProgressIndicator"
+                     Grid.Row="1"
+                     Minimum="0"
+                     Maximum="100"
+                     Value="0"
+                     Height="4"
+                     IsIndeterminate="False"
+                     Foreground="#F6F7FB"
+                     Background="#2C313D" />
+      </Grid>
+    </Border>
   </Grid>
 </Window>

LanMountainDesktop.Launcher/Views/SplashWindow.axaml.cs

@@ -1,88 +1,266 @@
+using System.Diagnostics;
+using Avalonia;
 using Avalonia.Controls;
 using Avalonia.Input;
 using Avalonia.Interactivity;
 using Avalonia.Markup.Xaml;
+using Avalonia.Media;
 using Avalonia.Threading;
 using LanMountainDesktop.Launcher.Services;
+using LanMountainDesktop.Shared.Contracts.Launcher;
 
 namespace LanMountainDesktop.Launcher.Views;
 
-/// <summary>
-/// 启动画面窗口 - 简洁设计
-/// </summary>
 public partial class SplashWindow : Window, ISplashStageReporter
 {
-    private int _versionTextClickCount = 0;
     private const int DebugModeClickThreshold = 5;
-    private bool _isDebugModeOpened = false;
+    private static readonly TimeSpan FadeAnimationDuration = TimeSpan.FromMilliseconds(160);
+    private static readonly TimeSpan SlideAnimationDuration = TimeSpan.FromMilliseconds(260);
+
+    private readonly StartupVisualMode _mode;
+    private int _versionTextClickCount;
+    private bool _isDebugModeOpened;
+    private bool _isOpened;
+    private bool _layoutConfigured;
+    private bool _dismissed;
+    private PixelPoint _targetPosition;
+    private PixelPoint _slideHiddenPosition;
 
     public SplashWindow()
+        : this(StartupVisualMode.Fade)
     {
-        AvaloniaXamlLoader.Load(this);
-        
-        // 延迟到窗口加载完成后再绑定事件
-        this.Loaded += OnWindowLoaded;
     }
 
-    /// <summary>
-    /// 窗口加载完成事件
-    /// </summary>
+    public SplashWindow(StartupVisualMode mode)
+    {
+        _mode = mode;
+        AvaloniaXamlLoader.Load(this);
+        Loaded += OnWindowLoaded;
+        Opened += OnWindowOpened;
+    }
+
     private void OnWindowLoaded(object? sender, RoutedEventArgs e)
     {
-        Console.WriteLine("[SplashWindow] Window loaded, binding events...");
-        
-        // 绑定版本文本点击事件（隐藏功能：点击5次打开开发者界面）
-        var versionTextBorder = this.FindControl<Border>("VersionTextBorder");
-        if (versionTextBorder is not null)
+        if (this.FindControl<Border>("VersionTextBorder") is { } versionBorder)
         {
-            versionTextBorder.PointerPressed += OnVersionTextClick;
-            Console.WriteLine("[SplashWindow] VersionTextBorder click event bound");
-        }
-        else
-        {
-            Console.Error.WriteLine("[SplashWindow] Failed to find VersionTextBorder!");
+            versionBorder.PointerPressed += OnVersionTextClick;
         }
     }
 
-    /// <summary>
-    /// 版本文本点击事件 - 连续点击5次打开开发者界面（隐藏功能）
-    /// </summary>
+    private async void OnWindowOpened(object? sender, EventArgs e)
+    {
+        if (_isOpened)
+        {
+            return;
+        }
+
+        _isOpened = true;
+        ConfigureForVisualMode();
+
+        if (_mode == StartupVisualMode.Fade)
+        {
+            Opacity = 0d;
+            await AnimateOpacityAsync(0d, 1d, FadeAnimationDuration).ConfigureAwait(false);
+            return;
+        }
+
+        Opacity = 1d;
+        if (_mode == StartupVisualMode.SlideSplash)
+        {
+            await AnimateWindowPositionAsync(_slideHiddenPosition, _targetPosition, SlideAnimationDuration, EaseOutCubic).ConfigureAwait(false);
+        }
+    }
+
+    public async Task DismissAsync()
+    {
+        if (_dismissed)
+        {
+            return;
+        }
+
+        _dismissed = true;
+        ConfigureForVisualMode();
+
+        if (_mode == StartupVisualMode.SlideSplash)
+        {
+            var from = Position;
+            await AnimateWindowPositionAsync(from, _slideHiddenPosition, SlideAnimationDuration, EaseInCubic).ConfigureAwait(false);
+        }
+        else if (_mode == StartupVisualMode.Fade)
+        {
+            await AnimateOpacityAsync(Opacity, 0d, FadeAnimationDuration).ConfigureAwait(false);
+        }
+
+        await Dispatcher.UIThread.InvokeAsync(() =>
+        {
+            if (IsVisible)
+            {
+                Close();
+            }
+        });
+    }
+
+    public void Report(string stage, string message)
+    {
+        Dispatcher.UIThread.Post(() =>
+        {
+            if (this.FindControl<TextBlock>("StatusText") is { } statusText)
+            {
+                statusText.Text = message;
+            }
+
+            if (this.FindControl<ProgressBar>("ProgressIndicator") is { } progressIndicator)
+            {
+                var progress = ResolveProgress(stage);
+                if (progress > 0)
+                {
+                    progressIndicator.IsIndeterminate = false;
+                    progressIndicator.Value = progress;
+                }
+                else
+                {
+                    progressIndicator.IsIndeterminate = true;
+                }
+            }
+        });
+    }
+
+    public void ReportStage(string stage, int progress)
+    {
+        Dispatcher.UIThread.Post(() =>
+        {
+            if (this.FindControl<TextBlock>("StatusText") is { } statusText)
+            {
+                statusText.Text = stage;
+            }
+
+            if (this.FindControl<ProgressBar>("ProgressIndicator") is { } progressIndicator)
+            {
+                progressIndicator.IsIndeterminate = false;
+                progressIndicator.Value = Math.Clamp(progress, 0, 100);
+            }
+        });
+    }
+
+    public void UpdateProgress(int percent, string? message = null)
+    {
+        Dispatcher.UIThread.Post(() =>
+        {
+            if (!string.IsNullOrWhiteSpace(message) &&
+                this.FindControl<TextBlock>("StatusText") is { } statusText)
+            {
+                statusText.Text = message;
+            }
+
+            if (this.FindControl<ProgressBar>("ProgressIndicator") is { } progressIndicator)
+            {
+                progressIndicator.IsIndeterminate = false;
+                progressIndicator.Value = Math.Clamp(percent, 0, 100);
+            }
+        });
+    }
+
+    public void UpdateStatus(string message)
+    {
+        Dispatcher.UIThread.Post(() =>
+        {
+            if (this.FindControl<TextBlock>("StatusText") is { } statusText)
+            {
+                statusText.Text = message;
+            }
+        });
+    }
+
+    public void SetVersionInfo(string version, string codename)
+    {
+        Dispatcher.UIThread.Post(() =>
+        {
+            if (this.FindControl<TextBlock>("VersionText") is { } versionText)
+            {
+                versionText.Text = $"{version} ({codename})";
+            }
+        });
+    }
+
+    public void SetDebugMode(bool isDebugMode)
+    {
+        if (!isDebugMode)
+        {
+            return;
+        }
+
+        UpdateStatus("[Debug Mode] Splash Preview");
+    }
+
+    private void ConfigureForVisualMode()
+    {
+        if (_layoutConfigured)
+        {
+            return;
+        }
+
+        _layoutConfigured = true;
+        var compactHero = this.FindControl<Grid>("CompactHero");
+        var fullscreenHero = this.FindControl<Grid>("FullscreenHero");
+
+        if (_mode == StartupVisualMode.Fade)
+        {
+            compactHero?.SetCurrentValue(IsVisibleProperty, true);
+            fullscreenHero?.SetCurrentValue(IsVisibleProperty, false);
+            Background = new SolidColorBrush(Color.Parse("#0B0B0B"));
+            Width = 480;
+            Height = 320;
+            WindowStartupLocation = WindowStartupLocation.CenterScreen;
+            return;
+        }
+
+        compactHero?.SetCurrentValue(IsVisibleProperty, false);
+        fullscreenHero?.SetCurrentValue(IsVisibleProperty, true);
+        Background = Brushes.Black;
+        WindowStartupLocation = WindowStartupLocation.Manual;
+
+        var screen = Screens?.Primary ?? Screens?.All.FirstOrDefault();
+        var workingArea = screen?.WorkingArea ?? new PixelRect(0, 0, 1920, 1080);
+        var scale = Math.Max(screen?.Scaling ?? 1d, 0.01d);
+
+        Width = workingArea.Width / scale;
+        Height = workingArea.Height / scale;
+        _targetPosition = new PixelPoint(workingArea.X, workingArea.Y);
+        _slideHiddenPosition = new PixelPoint(workingArea.X + workingArea.Width, workingArea.Y);
+        Position = _mode == StartupVisualMode.SlideSplash
+            ? _slideHiddenPosition
+            : _targetPosition;
+    }
+
     private void OnVersionTextClick(object? sender, PointerPressedEventArgs e)
     {
-        if (_isDebugModeOpened) return;
-        
-        _versionTextClickCount++;
-        Console.WriteLine($"[SplashWindow] Version text clicked {_versionTextClickCount}/{DebugModeClickThreshold}");
+        if (_isDebugModeOpened)
+        {
+            return;
+        }
 
+        _versionTextClickCount++;
         if (_versionTextClickCount >= DebugModeClickThreshold)
         {
             OpenDebugWindow();
         }
     }
 
-    /// <summary>
-    /// 打开开发者调试窗口
-    /// </summary>
     private async void OpenDebugWindow()
     {
         _isDebugModeOpened = true;
-        Console.WriteLine("[SplashWindow] Opening debug window...");
 
         try
         {
-            // 加载保存的状态
-            var devModeEnabled = ErrorWindow.CheckDevModeEnabled();
-            var customHostPath = ErrorWindow.GetSavedCustomHostPath();
-
-            var debugWindow = new ErrorDebugWindow(devModeEnabled, customHostPath)
+            var debugWindow = new ErrorDebugWindow(
+                ErrorWindow.CheckDevModeEnabled(),
+                ErrorWindow.GetSavedCustomHostPath())
             {
-                WindowStartupLocation = WindowStartupLocation.CenterScreen
+                WindowStartupLocation = WindowStartupLocation.CenterOwner
             };
 
-            // 订阅窗口关闭事件以保存状态
-            debugWindow.Closed += (s, e) =>
+            debugWindow.Closed += (_, _) =>
             {
-                Console.WriteLine("[SplashWindow] Debug window closed");
                 _isDebugModeOpened = false;
                 _versionTextClickCount = 0;
             };
@@ -91,160 +269,75 @@ public partial class SplashWindow : Window, ISplashStageReporter
         }
         catch (Exception ex)
         {
-            Console.Error.WriteLine($"[SplashWindow] Error opening debug window: {ex.Message}");
+            Debug.WriteLine($"[SplashWindow] Failed to open debug window: {ex}");
             _isDebugModeOpened = false;
             _versionTextClickCount = 0;
         }
     }
 
-    /// <summary>
-    /// 更新进度和状态
-    /// </summary>
-    public void Report(string stage, string message)
+    private async Task AnimateOpacityAsync(double from, double to, TimeSpan duration)
     {
-        Dispatcher.UIThread.Post(() =>
+        await AnimateAsync(progress =>
         {
-            var statusText = this.FindControl<TextBlock>("StatusText");
-            var progressIndicator = this.FindControl<ProgressBar>("ProgressIndicator");
-            
-            if (statusText is null || progressIndicator is null)
-            {
-                Console.Error.WriteLine($"[SplashWindow] Controls not found: StatusText={statusText != null}, ProgressIndicator={progressIndicator != null}");
-                return;
-            }
-
-            // 更新状态文本
-            statusText.Text = message;
-
-            // 根据阶段更新进度
-            var progress = ResolveProgress(stage);
-            if (progress > 0)
-            {
-                progressIndicator.IsIndeterminate = false;
-                progressIndicator.Value = progress;
-            }
-            else
-            {
-                progressIndicator.IsIndeterminate = true;
-            }
-        });
+            Opacity = from + ((to - from) * progress);
+        }, duration, EaseOutCubic).ConfigureAwait(false);
     }
 
-    /// <summary>
-    /// 更新进度（0-100）
-    /// </summary>
-    public void UpdateProgress(int percent, string? message = null)
+    private async Task AnimateWindowPositionAsync(
+        PixelPoint from,
+        PixelPoint to,
+        TimeSpan duration,
+        Func<double, double> easing)
     {
-        Dispatcher.UIThread.Post(() =>
+        await AnimateAsync(progress =>
         {
-            var statusText = this.FindControl<TextBlock>("StatusText");
-            var progressIndicator = this.FindControl<ProgressBar>("ProgressIndicator");
-            
-            if (statusText is null || progressIndicator is null)
-            {
-                Console.Error.WriteLine($"[SplashWindow] Controls not found in UpdateProgress");
-                return;
-            }
-
-            if (!string.IsNullOrEmpty(message))
-            {
-                statusText.Text = message;
-            }
-
-            progressIndicator.IsIndeterminate = false;
-            progressIndicator.Value = Math.Clamp(percent, 0, 100);
-        });
+            var currentX = (int)Math.Round(from.X + ((to.X - from.X) * progress));
+            var currentY = (int)Math.Round(from.Y + ((to.Y - from.Y) * progress));
+            Position = new PixelPoint(currentX, currentY);
+        }, duration, easing).ConfigureAwait(false);
     }
 
-    /// <summary>
-    /// 更新状态文本
-    /// </summary>
-    public void UpdateStatus(string message)
+    private async Task AnimateAsync(Action<double> update, TimeSpan duration, Func<double, double> easing)
     {
-        Dispatcher.UIThread.Post(() =>
+        if (duration <= TimeSpan.Zero)
         {
-            var statusText = this.FindControl<TextBlock>("StatusText");
-            if (statusText is null)
-            {
-                Console.Error.WriteLine($"[SplashWindow] StatusText not found in UpdateStatus");
-                return;
-            }
-            statusText.Text = message;
-        });
+            await Dispatcher.UIThread.InvokeAsync(() => update(1d));
+            return;
+        }
+
+        var stopwatch = Stopwatch.StartNew();
+        while (stopwatch.Elapsed < duration)
+        {
+            var raw = stopwatch.Elapsed.TotalMilliseconds / duration.TotalMilliseconds;
+            var progress = easing(Math.Clamp(raw, 0d, 1d));
+            await Dispatcher.UIThread.InvokeAsync(() => update(progress));
+            await Task.Delay(16).ConfigureAwait(false);
+        }
+
+        await Dispatcher.UIThread.InvokeAsync(() => update(1d));
     }
 
-    /// <summary>
-    /// 报告阶段和进度（0-100）
-    /// </summary>
-    public void ReportStage(string stage, int progress)
-    {
-        Dispatcher.UIThread.Post(() =>
-        {
-            var statusText = this.FindControl<TextBlock>("StatusText");
-            var progressIndicator = this.FindControl<ProgressBar>("ProgressIndicator");
-            
-            if (statusText is null || progressIndicator is null)
-            {
-                Console.Error.WriteLine($"[SplashWindow] Controls not found in ReportStage");
-                return;
-            }
-
-            statusText.Text = stage;
-            progressIndicator.IsIndeterminate = false;
-            progressIndicator.Value = Math.Clamp(progress, 0, 100);
-        });
-    }
-
-    /// <summary>
-    /// 设置版本和开发代号
-    /// </summary>
-    public void SetVersionInfo(string version, string codename)
-    {
-        Dispatcher.UIThread.Post(() =>
-        {
-            var versionText = this.FindControl<TextBlock>("VersionText");
-            if (versionText is null)
-            {
-                Console.Error.WriteLine($"[SplashWindow] VersionText not found in SetVersionInfo");
-                return;
-            }
-            versionText.Text = $"{version} ({codename})";
-        });
-    }
-
-    /// <summary>
-    /// 设置调试模式
-    /// </summary>
-    public void SetDebugMode(bool isDebugMode)
-    {
-        Dispatcher.UIThread.Post(() =>
-        {
-            var statusText = this.FindControl<TextBlock>("StatusText");
-            if (statusText is null)
-            {
-                Console.Error.WriteLine($"[SplashWindow] StatusText not found in SetDebugMode");
-                return;
-            }
-            if (isDebugMode)
-            {
-                statusText.Text = "[Debug Mode] Splash Preview";
-            }
-        });
-    }
-
-    /// <summary>
-    /// 根据阶段名称解析进度值
-    /// </summary>
     private static int ResolveProgress(string stage)
     {
         return stage.ToLowerInvariant() switch
         {
             "initializing" => 10,
+            "settings" => 25,
             "update" => 30,
             "plugins" => 50,
-            "launch" => 70,
+            "ui" => 65,
+            "shell" => 80,
+            "activation" => 90,
             "ready" => 100,
             _ => 0
         };
     }
+
+    private static double EaseOutCubic(double value)
+    {
+        var inverse = 1d - value;
+        return 1d - (inverse * inverse * inverse);
+    }
+
+    private static double EaseInCubic(double value) => value * value * value;
 }

LanMountainDesktop.Shared.Contracts/Launcher/LoadingState.cs

@@ -1,231 +1,85 @@
 namespace LanMountainDesktop.Shared.Contracts.Launcher;
 
-/// <summary>
-/// 加载项类型
-/// </summary>
 public enum LoadingItemType
 {
-    /// <summary>
-    /// 系统初始化
-    /// </summary>
     System,
-    
-    /// <summary>
-    /// 设置加载
-    /// </summary>
     Settings,
-    
-    /// <summary>
-    /// 插件
-    /// </summary>
     Plugin,
-    
-    /// <summary>
-    /// 组件
-    /// </summary>
     Component,
-    
-    /// <summary>
-    /// 资源
-    /// </summary>
     Resource,
-    
-    /// <summary>
-    /// 数据
-    /// </summary>
     Data,
-    
-    /// <summary>
-    /// 网络请求
-    /// </summary>
     Network,
-    
-    /// <summary>
-    /// 其他
-    /// </summary>
     Other
 }
 
-/// <summary>
-/// 加载状态
-/// </summary>
 public enum LoadingState
 {
-    /// <summary>
-    /// 等待中
-    /// </summary>
     Pending,
-    
-    /// <summary>
-    /// 进行中
-    /// </summary>
     InProgress,
-    
-    /// <summary>
-    /// 已完成
-    /// </summary>
     Completed,
-    
-    /// <summary>
-    /// 失败
-    /// </summary>
+    Delayed,
     Failed,
-    
-    /// <summary>
-    /// 已取消
-    /// </summary>
     Cancelled,
-    
-    /// <summary>
-    /// 超时
-    /// </summary>
     Timeout
 }
 
-/// <summary>
-/// 加载项信息
-/// </summary>
 public record LoadingItem
 {
-    /// <summary>
-    /// 加载项唯一标识
-    /// </summary>
     public required string Id { get; init; }
-    
-    /// <summary>
-    /// 加载项类型
-    /// </summary>
+
     public LoadingItemType Type { get; init; }
-    
-    /// <summary>
-    /// 加载项名称
-    /// </summary>
+
     public required string Name { get; init; }
-    
-    /// <summary>
-    /// 加载项描述
-    /// </summary>
+
     public string? Description { get; init; }
-    
-    /// <summary>
-    /// 当前状态
-    /// </summary>
+
     public LoadingState State { get; init; }
-    
-    /// <summary>
-    /// 进度百分比 (0-100)
-    /// </summary>
+
     public int ProgressPercent { get; init; }
-    
-    /// <summary>
-    /// 状态消息
-    /// </summary>
+
     public string? Message { get; init; }
-    
-    /// <summary>
-    /// 错误信息（当 State 为 Failed 时）
-    /// </summary>
+
     public string? ErrorMessage { get; init; }
-    
-    /// <summary>
-    /// 开始时间
-    /// </summary>
+
     public DateTimeOffset? StartTime { get; init; }
-    
-    /// <summary>
-    /// 结束时间
-    /// </summary>
+
     public DateTimeOffset? EndTime { get; init; }
-    
-    /// <summary>
-    /// 预计剩余时间（秒）
-    /// </summary>
+
     public int? EstimatedRemainingSeconds { get; init; }
-    
-    /// <summary>
-    /// 子加载项
-    /// </summary>
+
     public List<LoadingItem>? Children { get; init; }
-    
-    /// <summary>
-    /// 额外数据
-    /// </summary>
+
     public Dictionary<string, string>? Metadata { get; init; }
-    
-    /// <summary>
-    /// 时间戳
-    /// </summary>
+
     public DateTimeOffset Timestamp { get; init; } = DateTimeOffset.UtcNow;
 }
 
-/// <summary>
-/// 加载状态更新消息
-/// </summary>
 public record LoadingStateMessage
 {
-    /// <summary>
-    /// 当前启动阶段
-    /// </summary>
     public StartupStage Stage { get; init; }
-    
-    /// <summary>
-    /// 整体进度百分比 (0-100)
-    /// </summary>
+
     public int OverallProgressPercent { get; init; }
-    
-    /// <summary>
-    /// 当前活动的加载项
-    /// </summary>
+
     public List<LoadingItem> ActiveItems { get; init; } = new();
-    
-    /// <summary>
-    /// 已完成的加载项数量
-    /// </summary>
+
     public int CompletedCount { get; init; }
-    
-    /// <summary>
-    /// 总加载项数量
-    /// </summary>
+
     public int TotalCount { get; init; }
-    
-    /// <summary>
-    /// 状态消息
-    /// </summary>
+
     public string? Message { get; init; }
-    
-    /// <summary>
-    /// 是否有错误
-    /// </summary>
+
     public bool HasErrors { get; init; }
-    
-    /// <summary>
-    /// 错误消息列表
-    /// </summary>
+
     public List<string>? ErrorMessages { get; init; }
-    
-    /// <summary>
-    /// 时间戳
-    /// </summary>
+
     public DateTimeOffset Timestamp { get; init; } = DateTimeOffset.UtcNow;
 }
 
-/// <summary>
-/// 详细的加载进度消息（用于实时更新）
-/// </summary>
 public record DetailedProgressMessage : StartupProgressMessage
 {
-    /// <summary>
-    /// 当前加载项
-    /// </summary>
     public LoadingItem? CurrentItem { get; init; }
-    
-    /// <summary>
-    /// 所有加载项
-    /// </summary>
+
     public List<LoadingItem>? AllItems { get; init; }
-    
-    /// <summary>
-    /// 是否为主要更新
-    /// </summary>
+
     public bool IsMajorUpdate { get; init; }
 }

LanMountainDesktop.Shared.Contracts/Launcher/StartupVisualPreferences.cs

@@ -0,0 +1,91 @@
+using System.Text.Json;
+
+namespace LanMountainDesktop.Shared.Contracts.Launcher;
+
+public enum StartupVisualMode
+{
+    Fade,
+    StaticSplash,
+    SlideSplash
+}
+
+public readonly record struct StartupVisualPreferences(
+    bool EnableFadeTransition,
+    bool EnableSlideTransition)
+{
+    public static StartupVisualPreferences Default => new(true, false);
+
+    public StartupVisualPreferences Normalize()
+    {
+        if (EnableSlideTransition)
+        {
+            return new StartupVisualPreferences(false, true);
+        }
+
+        return new StartupVisualPreferences(EnableFadeTransition, false);
+    }
+
+    public StartupVisualMode Mode => Normalize() switch
+    {
+        { EnableSlideTransition: true } => StartupVisualMode.SlideSplash,
+        { EnableFadeTransition: false } => StartupVisualMode.StaticSplash,
+        _ => StartupVisualMode.Fade
+    };
+}
+
+public static class StartupVisualPreferencesResolver
+{
+    public static StartupVisualPreferences Resolve(string? settingsPath = null)
+    {
+        var resolvedPath = string.IsNullOrWhiteSpace(settingsPath)
+            ? GetDefaultSettingsPath()
+            : settingsPath!;
+
+        if (!File.Exists(resolvedPath))
+        {
+            return StartupVisualPreferences.Default;
+        }
+
+        try
+        {
+            using var stream = File.OpenRead(resolvedPath);
+            using var document = JsonDocument.Parse(stream);
+            var root = document.RootElement;
+
+            var enableFade = TryGetBoolean(root, "enableFadeTransition") ?? true;
+            var enableSlide = TryGetBoolean(root, "enableSlideTransition") ?? false;
+            return FromFlags(enableFade, enableSlide);
+        }
+        catch
+        {
+            return StartupVisualPreferences.Default;
+        }
+    }
+
+    public static StartupVisualPreferences FromFlags(bool enableFadeTransition, bool enableSlideTransition)
+    {
+        return new StartupVisualPreferences(enableFadeTransition, enableSlideTransition).Normalize();
+    }
+
+    public static string GetDefaultSettingsPath()
+    {
+        var appData = Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData);
+        return Path.Combine(appData, "LanMountainDesktop", "settings.json");
+    }
+
+    private static bool? TryGetBoolean(JsonElement root, string propertyName)
+    {
+        if (!root.TryGetProperty(propertyName, out var property))
+        {
+            return null;
+        }
+
+        return property.ValueKind switch
+        {
+            JsonValueKind.True => true,
+            JsonValueKind.False => false,
+            JsonValueKind.String when bool.TryParse(property.GetString(), out var value) => value,
+            _ => null
+        };
+    }
+}

LanMountainDesktop.Shared.IPC/Abstractions/Services/IPublicShellControlService.cs

@@ -5,8 +5,16 @@ namespace LanMountainDesktop.Shared.IPC.Abstractions.Services;
 [IpcPublic(IgnoresIpcException = true)]
 public interface IPublicShellControlService
 {
+    Task<PublicShellStatus> GetShellStatusAsync();
+
     Task<bool> ActivateMainWindowAsync();
 
+    Task<PublicShellActivationResult> ActivateMainWindowWithStatusAsync();
+
+    Task<PublicTrayStatus> EnsureTrayReadyAsync();
+
+    Task<PublicTaskbarStatus> EnsureTaskbarEntryAsync();
+
     Task<bool> OpenSettingsAsync(string? pageTag = null);
 
     Task<bool> RestartAsync();

LanMountainDesktop.Shared.IPC/Abstractions/Services/PublicShellStatus.cs

@@ -0,0 +1,36 @@
+namespace LanMountainDesktop.Shared.IPC.Abstractions.Services;
+
+public sealed record PublicShellStatus(
+    int ProcessId,
+    DateTimeOffset StartedAtUtc,
+    string LaunchSource,
+    string ShellState,
+    bool MainWindowCreated,
+    bool MainWindowVisible,
+    bool MainWindowOpened,
+    bool DesktopVisible,
+    bool PublicIpcReady,
+    PublicTrayStatus Tray,
+    PublicTaskbarStatus Taskbar);
+
+public sealed record PublicTrayStatus(
+    string State,
+    bool IsReady,
+    bool HasIcon,
+    bool HasMenu,
+    bool IsVisible,
+    int ConsecutiveRecoveryFailures);
+
+public sealed record PublicTaskbarStatus(
+    bool RequestedBySettings,
+    bool MainWindowExists,
+    bool MainWindowShowInTaskbar,
+    bool MainWindowVisible,
+    bool MainWindowMinimized,
+    bool IsUsable);
+
+public sealed record PublicShellActivationResult(
+    bool Accepted,
+    string Code,
+    string Message,
+    PublicShellStatus Status);

LanMountainDesktop.Tests/LauncherCoordinatorRegistryTests.cs

@@ -0,0 +1,126 @@
+using System.Text.Json.Nodes;
+using LanMountainDesktop.Launcher.Models;
+using LanMountainDesktop.Launcher.Services;
+using LanMountainDesktop.Shared.Contracts.Launcher;
+using Xunit;
+
+namespace LanMountainDesktop.Tests;
+
+public sealed class LauncherCoordinatorRegistryTests
+{
+    [Fact]
+    public void TryReserveCoordinator_WhenActiveCoordinatorExists_ReturnsActiveAttempt()
+    {
+        using var temp = TemporaryAttemptState.Create();
+        var firstRegistry = new StartupAttemptRegistry(temp.StatePath);
+        var secondRegistry = new StartupAttemptRegistry(temp.StatePath);
+
+        Assert.True(firstRegistry.TryReserveCoordinator(
+            "normal",
+            "Foreground",
+            "pipe-a",
+            out var firstAttempt,
+            out var firstActive));
+        Assert.Null(firstActive);
+
+        Assert.False(secondRegistry.TryReserveCoordinator(
+            "normal",
+            "Foreground",
+            "pipe-b",
+            out _,
+            out var secondActive));
+
+        Assert.NotNull(secondActive);
+        Assert.Equal(firstAttempt.AttemptId, secondActive.AttemptId);
+        Assert.Equal("pipe-a", secondActive.CoordinatorPipeName);
+        Assert.Equal(Environment.ProcessId, secondActive.CoordinatorPid);
+    }
+
+    [Fact]
+    public void TryReserveCoordinator_WhenHeartbeatIsStale_TakesOverAttempt()
+    {
+        using var temp = TemporaryAttemptState.Create();
+        var firstRegistry = new StartupAttemptRegistry(temp.StatePath);
+        var secondRegistry = new StartupAttemptRegistry(temp.StatePath);
+
+        Assert.True(firstRegistry.TryReserveCoordinator(
+            "normal",
+            "Foreground",
+            "pipe-a",
+            out var firstAttempt,
+            out _));
+        temp.SetHeartbeat(DateTimeOffset.UtcNow.AddSeconds(-30));
+
+        Assert.True(secondRegistry.TryReserveCoordinator(
+            "normal",
+            "Foreground",
+            "pipe-b",
+            out var reservedAttempt,
+            out var activeAttempt));
+
+        Assert.Null(activeAttempt);
+        Assert.Equal(firstAttempt.AttemptId, reservedAttempt.AttemptId);
+        Assert.Equal("pipe-b", reservedAttempt.CoordinatorPipeName);
+    }
+
+    [Fact]
+    public void AssignOwnedHostProcess_ClearsReservedBeforeHostStart()
+    {
+        using var temp = TemporaryAttemptState.Create();
+        var registry = new StartupAttemptRegistry(temp.StatePath);
+
+        Assert.True(registry.TryReserveCoordinator(
+            "normal",
+            "Foreground",
+            "pipe-a",
+            out var reservedAttempt,
+            out _));
+        Assert.True(reservedAttempt.ReservedBeforeHostStart);
+
+        var assignedAttempt = registry.AssignOwnedHostProcess(
+            Environment.ProcessId,
+            StartupStage.Initializing,
+            "host assigned");
+
+        Assert.Equal(Environment.ProcessId, assignedAttempt.HostPid);
+        Assert.False(assignedAttempt.ReservedBeforeHostStart);
+    }
+
+    private sealed class TemporaryAttemptState : IDisposable
+    {
+        private TemporaryAttemptState(string directory)
+        {
+            Directory = directory;
+            StatePath = Path.Combine(directory, "startup-attempt.json");
+        }
+
+        public string Directory { get; }
+
+        public string StatePath { get; }
+
+        public static TemporaryAttemptState Create()
+        {
+            var directory = Path.Combine(
+                Path.GetTempPath(),
+                "LanMountainDesktop.LauncherCoordinatorTests",
+                Guid.NewGuid().ToString("N"));
+            System.IO.Directory.CreateDirectory(directory);
+            return new TemporaryAttemptState(directory);
+        }
+
+        public void SetHeartbeat(DateTimeOffset heartbeatAtUtc)
+        {
+            var node = JsonNode.Parse(File.ReadAllText(StatePath))!.AsObject();
+            node["heartbeatAtUtc"] = heartbeatAtUtc.ToString("O");
+            File.WriteAllText(StatePath, node.ToJsonString());
+        }
+
+        public void Dispose()
+        {
+            if (System.IO.Directory.Exists(Directory))
+            {
+                System.IO.Directory.Delete(Directory, recursive: true);
+            }
+        }
+    }
+}

LanMountainDesktop.Tests/StartupVisualPreferencesTests.cs

@@ -0,0 +1,57 @@
+using LanMountainDesktop.Shared.Contracts.Launcher;
+using Xunit;
+
+namespace LanMountainDesktop.Tests;
+
+public sealed class StartupVisualPreferencesTests
+{
+    [Fact]
+    public void FromFlags_WhenSlideEnabled_DisablesFadeAndUsesSlideMode()
+    {
+        var preferences = StartupVisualPreferencesResolver.FromFlags(
+            enableFadeTransition: true,
+            enableSlideTransition: true);
+
+        Assert.False(preferences.EnableFadeTransition);
+        Assert.True(preferences.EnableSlideTransition);
+        Assert.Equal(StartupVisualMode.SlideSplash, preferences.Mode);
+    }
+
+    [Fact]
+    public void FromFlags_WhenFadeDisabledAndSlideDisabled_UsesStaticSplashMode()
+    {
+        var preferences = StartupVisualPreferencesResolver.FromFlags(
+            enableFadeTransition: false,
+            enableSlideTransition: false);
+
+        Assert.False(preferences.EnableFadeTransition);
+        Assert.False(preferences.EnableSlideTransition);
+        Assert.Equal(StartupVisualMode.StaticSplash, preferences.Mode);
+    }
+
+    [Fact]
+    public void Resolve_WhenFadeSettingMissing_DefaultsToFadeEnabled()
+    {
+        var tempDirectory = Path.Combine(Path.GetTempPath(), "LanMountainDesktop.StartupVisualTests", Guid.NewGuid().ToString("N"));
+        Directory.CreateDirectory(tempDirectory);
+        var settingsPath = Path.Combine(tempDirectory, "settings.json");
+        File.WriteAllText(settingsPath, """
+        {
+          "enableSlideTransition": false
+        }
+        """);
+
+        try
+        {
+            var preferences = StartupVisualPreferencesResolver.Resolve(settingsPath);
+
+            Assert.True(preferences.EnableFadeTransition);
+            Assert.False(preferences.EnableSlideTransition);
+            Assert.Equal(StartupVisualMode.Fade, preferences.Mode);
+        }
+        finally
+        {
+            Directory.Delete(tempDirectory, recursive: true);
+        }
+    }
+}

LanMountainDesktop/App.axaml.cs

@@ -71,6 +71,7 @@ public partial class App : Application
     private ShutdownIntent _shutdownIntent;
 
     private DesktopTrayService? _desktopTrayService;
+    private DispatcherTimer? _shellRecoveryTimer;
     private PluginRuntimeService? _pluginRuntimeService;
     private MainWindow? _mainWindow;
     private TransparentOverlayWindow? _transparentOverlayWindow;
@@ -478,6 +479,7 @@ public partial class App : Application
     private void InitializeTrayIcon()
     {
         EnsureDesktopTrayService();
+        _desktopTrayService?.StartWatchdog();
         _trayInitialized = _desktopTrayService?.EnsureReady("Startup") == true;
         if (_trayInitialized)
         {
@@ -525,14 +527,67 @@ public partial class App : Application
             OnTrayRestartClick,
             OnTrayExitClick);
         _desktopTrayService.StateChanged += OnTrayAvailabilityStateChanged;
+        _desktopTrayService.StartWatchdog();
+        EnsureShellRecoveryWatchdog();
+    }
+
+    private void EnsureShellRecoveryWatchdog()
+    {
+        _shellRecoveryTimer ??= new DispatcherTimer(
+            TimeSpan.FromSeconds(10),
+            DispatcherPriority.Background,
+            OnShellRecoveryWatchdogTick);
+
+        if (!_shellRecoveryTimer.IsEnabled)
+        {
+            _shellRecoveryTimer.Start();
+        }
+    }
+
+    private void StopShellRecoveryWatchdog()
+    {
+        if (_shellRecoveryTimer?.IsEnabled == true)
+        {
+            _shellRecoveryTimer.Stop();
+        }
+    }
+
+    private void OnShellRecoveryWatchdogTick(object? sender, EventArgs e)
+    {
+        _ = sender;
+        _ = e;
+
+        if (_shutdownIntent != ShutdownIntent.None)
+        {
+            return;
+        }
+
+        EnsureTrayReady("ShellRecoveryWatchdog");
+
+        if (!ShouldShowMainWindowInTaskbar())
+        {
+            return;
+        }
+
+        if (_desktopShellState != DesktopShellState.ForegroundDesktop)
+        {
+            EnsureTaskbarEntry("ShellRecoveryWatchdog");
+            return;
+        }
+
+        if (_mainWindow is not null && _mainWindow.IsVisible && !_mainWindow.ShowInTaskbar)
+        {
+            _mainWindow.ShowInTaskbar = true;
+        }
     }
 
     private bool EnsureTrayReady(string reason)
     {
         EnsureDesktopTrayService();
+        var wasReady = _trayInitialized;
         var ready = _desktopTrayService?.EnsureReady(reason) == true;
         _trayInitialized = ready;
-        if (ready)
+        if (ready && !wasReady)
         {
             ReportStartupProgress(StartupStage.TrayReady, 75, "Tray ready.");
         }
@@ -544,9 +599,25 @@ public partial class App : Application
     {
         _trayInitialized = state == TrayAvailabilityState.Ready;
 
-        if (state == TrayAvailabilityState.Failed && _desktopShellState == DesktopShellState.TrayOnly)
+        if (state != TrayAvailabilityState.Failed)
+        {
+            return;
+        }
+
+        if (_desktopShellState == DesktopShellState.TrayOnly)
         {
             RestoreOrCreateMainWindow(showSingleInstanceNotice: false, source: "TrayAvailabilityFailed");
+            return;
+        }
+
+        var foregroundVisible = _mainWindow?.IsVisible == true &&
+                                _mainWindow.WindowState != WindowState.Minimized;
+        var taskbarUsable = BuildPublicTaskbarStatus().IsUsable;
+        if (!foregroundVisible &&
+            !taskbarUsable &&
+            (_desktopTrayService?.ConsecutiveRecoveryFailures ?? 0) >= 3)
+        {
+            RestoreOrCreateMainWindow(showSingleInstanceNotice: false, source: "TrayAvailabilityRepeatedFailure");
         }
     }
 
@@ -719,7 +790,10 @@ public partial class App : Application
                 mainWindow.WindowState = WindowState.Normal;
             }
 
-            if (mainWindow.WindowState != WindowState.FullScreen)
+            mainWindow.EnsureForegroundWindowLayout();
+
+            if (mainWindow.ShouldUseFullscreenWindow() &&
+                mainWindow.WindowState != WindowState.FullScreen)
             {
                 mainWindow.WindowState = WindowState.FullScreen;
             }
@@ -733,7 +807,6 @@ public partial class App : Application
                 mainWindow.PlayEnterAnimation();
             }, DispatcherPriority.Background);
 
-            _desktopTrayService?.StopWatchdog();
             SetDesktopShellState(DesktopShellState.ForegroundDesktop, $"Restore:{source}");
             AppLogger.Info(
                 "DesktopShell",
@@ -861,6 +934,23 @@ public partial class App : Application
             {
                 RefreshFusedDesktopMenuItemVisibility();
             }
+
+            var showInTaskbarChanged =
+                refreshAll ||
+                changedKeys.Contains(nameof(AppSettingsSnapshot.ShowInTaskbar), StringComparer.OrdinalIgnoreCase);
+
+            if (showInTaskbarChanged)
+            {
+                EnsureTrayReady("SettingsChanged");
+                if (ShouldShowMainWindowInTaskbar())
+                {
+                    EnsureTaskbarEntry("SettingsChanged");
+                }
+                else if (_mainWindow is not null && _mainWindow.IsVisible)
+                {
+                    _mainWindow.ShowInTaskbar = false;
+                }
+            }
         }, DispatcherPriority.Background);
     }
 
@@ -977,6 +1067,7 @@ public partial class App : Application
         }
 
         _exitCleanupCompleted = true;
+        StopShellRecoveryWatchdog();
         _settingsFacade.Settings.Changed -= OnSettingsChanged;
         _appearanceThemeService.Changed -= OnAppearanceThemeChanged;
 
@@ -1155,7 +1246,6 @@ public partial class App : Application
             case RestartPresentationMode.Minimized:
                 mainWindow.ShowInTaskbar = true;
                 mainWindow.WindowState = WindowState.Minimized;
-                _desktopTrayService?.StopWatchdog();
                 SetDesktopShellState(DesktopShellState.MinimizedToTaskbar, "StartupRestartPresentation");
                 ReportStartupProgressSync(StartupStage.BackgroundReady, 95, "Background ready.");
                 return true;
@@ -1297,6 +1387,24 @@ public partial class App : Application
     {
         try
         {
+            if (ShouldShowMainWindowInTaskbar())
+            {
+                EnsureTrayReady($"TaskbarBackground:{source}");
+                mainWindow.ShowInTaskbar = true;
+                if (!mainWindow.IsVisible)
+                {
+                    mainWindow.Show();
+                }
+
+                mainWindow.WindowState = WindowState.Minimized;
+                SetDesktopShellState(DesktopShellState.MinimizedToTaskbar, source);
+                ReportStartupProgress(StartupStage.BackgroundReady, 95, "Background ready via taskbar.");
+                AppLogger.Info(
+                    "DesktopShell",
+                    $"Main window minimized to taskbar because taskbar entry is enabled. Source='{source}'.");
+                return;
+            }
+
             if (!EnsureTrayReady($"HideToTray:{source}"))
             {
                 RecoverFromTrayUnavailable(mainWindow, source);
@@ -1305,7 +1413,6 @@ public partial class App : Application
 
             mainWindow.ShowInTaskbar = false;
             mainWindow.Hide();
-            _desktopTrayService?.StartWatchdog();
             SetDesktopShellState(DesktopShellState.TrayOnly, source);
             ReportStartupProgress(StartupStage.BackgroundReady, 95, "Background ready.");
             AppLogger.Info(
@@ -1342,7 +1449,6 @@ public partial class App : Application
             }
 
             mainWindow.WindowState = WindowState.Minimized;
-            _desktopTrayService?.StopWatchdog();
             SetDesktopShellState(DesktopShellState.MinimizedToTaskbar, $"TrayFallbackTaskbar:{source}");
             ReportStartupProgress(StartupStage.BackgroundReady, 95, "Background ready via taskbar fallback.");
             return;
@@ -1359,7 +1465,10 @@ public partial class App : Application
             mainWindow.WindowState = WindowState.Normal;
         }
 
-        if (mainWindow.WindowState != WindowState.FullScreen)
+        mainWindow.EnsureForegroundWindowLayout();
+
+        if (mainWindow.ShouldUseFullscreenWindow() &&
+            mainWindow.WindowState != WindowState.FullScreen)
         {
             mainWindow.WindowState = WindowState.FullScreen;
         }
@@ -1367,7 +1476,6 @@ public partial class App : Application
         mainWindow.Activate();
         mainWindow.Topmost = true;
         mainWindow.Topmost = false;
-        _desktopTrayService?.StopWatchdog();
         SetDesktopShellState(DesktopShellState.ForegroundDesktop, $"TrayFallbackForeground:{source}");
         ReportStartupProgress(StartupStage.DesktopVisible, 100, "Desktop restored because tray was unavailable.");
     }
@@ -1377,6 +1485,48 @@ public partial class App : Application
         return _settingsFacade.Settings.LoadSnapshot<AppSettingsSnapshot>(SettingsScope.App).ShowInTaskbar;
     }
 
+    private bool EnsureTaskbarEntry(string source)
+    {
+        if (!ShouldShowMainWindowInTaskbar())
+        {
+            return false;
+        }
+
+        if (ApplicationLifetime is not IClassicDesktopStyleApplicationLifetime desktop)
+        {
+            AppLogger.Warn("DesktopShell", $"Taskbar repair skipped because desktop lifetime is unavailable. Source='{source}'.");
+            return false;
+        }
+
+        try
+        {
+            var mainWindow = GetOrCreateMainWindow(desktop, $"TaskbarRepair:{source}");
+            mainWindow.ShowInTaskbar = true;
+
+            if (!mainWindow.IsVisible)
+            {
+                mainWindow.Show();
+            }
+
+            if (_desktopShellState != DesktopShellState.ForegroundDesktop)
+            {
+                mainWindow.WindowState = WindowState.Minimized;
+                SetDesktopShellState(DesktopShellState.MinimizedToTaskbar, $"TaskbarRepair:{source}");
+                ReportStartupProgress(StartupStage.BackgroundReady, 95, "Background ready via taskbar repair.");
+            }
+
+            AppLogger.Info(
+                "DesktopShell",
+                $"Taskbar entry ensured. Source='{source}'; IsVisible={mainWindow.IsVisible}; ShowInTaskbar={mainWindow.ShowInTaskbar}; WindowState='{mainWindow.WindowState}'.");
+            return true;
+        }
+        catch (Exception ex)
+        {
+            AppLogger.Warn("DesktopShell", $"Failed to ensure taskbar entry. Source='{source}'.", ex);
+            return false;
+        }
+    }
+
     private void SetDesktopShellState(DesktopShellState state, string source)
     {
         if (_desktopShellState == state)
@@ -1428,7 +1578,72 @@ public partial class App : Application
 
     internal bool TryActivateMainWindowFromExternalIpc(string source)
     {
-        return RestoreOrCreateMainWindowCore(showSingleInstanceNotice: false, source);
+        return TryActivateMainWindowWithStatusFromExternalIpc(source).Accepted;
+    }
+
+    internal PublicShellActivationResult TryActivateMainWindowWithStatusFromExternalIpc(string source)
+    {
+        var restored = RestoreOrCreateMainWindowCore(showSingleInstanceNotice: false, source);
+        var status = GetPublicShellStatus();
+        return restored
+            ? new PublicShellActivationResult(true, "activated", "Desktop window activation was requested.", status)
+            : new PublicShellActivationResult(false, "activation_failed", "Desktop window activation failed.", status);
+    }
+
+    internal PublicTrayStatus EnsureTrayReadyFromExternalIpc(string source)
+    {
+        EnsureTrayReady($"ExternalIpc:{source}");
+        return BuildPublicTrayStatus();
+    }
+
+    internal PublicTaskbarStatus EnsureTaskbarEntryFromExternalIpc(string source)
+    {
+        EnsureTaskbarEntry($"ExternalIpc:{source}");
+        return BuildPublicTaskbarStatus();
+    }
+
+    internal PublicShellStatus GetPublicShellStatus()
+    {
+        return new PublicShellStatus(
+            Environment.ProcessId,
+            _startupAt,
+            _launchSource,
+            _desktopShellState.ToString(),
+            _mainWindow is not null && !_mainWindowClosed,
+            _mainWindow?.IsVisible == true,
+            _mainWindowOpened,
+            _mainWindow?.IsVisible == true && _mainWindow.WindowState != WindowState.Minimized,
+            _publicIpcHostService is not null,
+            BuildPublicTrayStatus(),
+            BuildPublicTaskbarStatus());
+    }
+
+    private PublicTrayStatus BuildPublicTrayStatus()
+    {
+        return new PublicTrayStatus(
+            _desktopTrayService?.State.ToString() ?? TrayAvailabilityState.Unavailable.ToString(),
+            _desktopTrayService?.IsReady == true,
+            _desktopTrayService?.HasIcon == true,
+            _desktopTrayService?.HasMenu == true,
+            _desktopTrayService?.IsVisible == true,
+            _desktopTrayService?.ConsecutiveRecoveryFailures ?? 0);
+    }
+
+    private PublicTaskbarStatus BuildPublicTaskbarStatus()
+    {
+        var requested = ShouldShowMainWindowInTaskbar();
+        var mainWindowExists = _mainWindow is not null && !_mainWindowClosed;
+        var showInTaskbar = _mainWindow?.ShowInTaskbar == true;
+        var visible = _mainWindow?.IsVisible == true;
+        var minimized = _mainWindow?.WindowState == WindowState.Minimized;
+
+        return new PublicTaskbarStatus(
+            requested,
+            mainWindowExists,
+            showInTaskbar,
+            visible,
+            minimized,
+            requested && mainWindowExists && showInTaskbar && visible);
     }
 
     private void InitializePublicIpc()

LanMountainDesktop/Models/AppSettingsSnapshot.cs

@@ -152,6 +152,8 @@ public sealed class AppSettingsSnapshot
 
     public bool EnableThreeFingerSwipe { get; set; } = false;
 
+    public bool EnableFadeTransition { get; set; } = true;
+
     public bool EnableSlideTransition { get; set; } = false;
 
     public bool ShowInTaskbar { get; set; } = false;

LanMountainDesktop/Services/DesktopTrayService.cs

@@ -34,6 +34,7 @@ internal sealed class DesktopTrayService : IDisposable
     private NativeMenuItem? _restartMenuItem;
     private NativeMenuItem? _exitMenuItem;
     private int _consecutiveRecoveryFailures;
+    private bool _disposed;
 
     public DesktopTrayService(
         Application application,
@@ -63,6 +64,14 @@ internal sealed class DesktopTrayService : IDisposable
 
     public bool IsReady => State == TrayAvailabilityState.Ready;
 
+    public bool HasIcon => _trayIcon?.Icon is not null;
+
+    public bool HasMenu => _trayIcon?.Menu is not null;
+
+    public bool IsVisible => _trayIcon?.IsVisible == true;
+
+    public int ConsecutiveRecoveryFailures => _consecutiveRecoveryFailures;
+
     public event Action<TrayAvailabilityState>? StateChanged;
 
     public bool EnsureReady(string reason)
@@ -105,6 +114,7 @@ internal sealed class DesktopTrayService : IDisposable
 
     public void Dispose()
     {
+        _disposed = true;
         StopWatchdog();
 
         try
@@ -126,7 +136,7 @@ internal sealed class DesktopTrayService : IDisposable
         _ = sender;
         _ = e;
 
-        if (State == TrayAvailabilityState.Unavailable || State == TrayAvailabilityState.Failed)
+        if (_disposed || State == TrayAvailabilityState.Unavailable)
         {
             return;
         }
@@ -256,6 +266,11 @@ internal sealed class DesktopTrayService : IDisposable
     {
         if (State == state)
         {
+            if (state == TrayAvailabilityState.Failed)
+            {
+                StateChanged?.Invoke(state);
+            }
+
             return;
         }
 

LanMountainDesktop/Services/ExternalIpc/PublicShellControlService.cs

@@ -7,6 +7,15 @@ namespace LanMountainDesktop.Services.ExternalIpc;
 
 internal sealed class PublicShellControlService : IPublicShellControlService
 {
+    public Task<PublicShellStatus> GetShellStatusAsync()
+    {
+        return Dispatcher.UIThread.InvokeAsync(() =>
+        {
+            return (Application.Current as App)?.GetPublicShellStatus()
+                ?? CreateUnavailableStatus();
+        }).GetTask();
+    }
+
     public Task<bool> ActivateMainWindowAsync()
     {
         return Dispatcher.UIThread.InvokeAsync(() =>
@@ -15,6 +24,37 @@ internal sealed class PublicShellControlService : IPublicShellControlService
         }).GetTask();
     }
 
+    public Task<PublicShellActivationResult> ActivateMainWindowWithStatusAsync()
+    {
+        return Dispatcher.UIThread.InvokeAsync(() =>
+        {
+            return (Application.Current as App)?.TryActivateMainWindowWithStatusFromExternalIpc("PublicIpc")
+                ?? new PublicShellActivationResult(
+                    false,
+                    "app_unavailable",
+                    "Application instance is not available.",
+                    CreateUnavailableStatus());
+        }).GetTask();
+    }
+
+    public Task<PublicTrayStatus> EnsureTrayReadyAsync()
+    {
+        return Dispatcher.UIThread.InvokeAsync(() =>
+        {
+            return (Application.Current as App)?.EnsureTrayReadyFromExternalIpc("PublicIpc")
+                ?? new PublicTrayStatus("Unavailable", false, false, false, false, 0);
+        }).GetTask();
+    }
+
+    public Task<PublicTaskbarStatus> EnsureTaskbarEntryAsync()
+    {
+        return Dispatcher.UIThread.InvokeAsync(() =>
+        {
+            return (Application.Current as App)?.EnsureTaskbarEntryFromExternalIpc("PublicIpc")
+                ?? new PublicTaskbarStatus(false, false, false, false, false, false);
+        }).GetTask();
+    }
+
     public Task<bool> OpenSettingsAsync(string? pageTag = null)
     {
         return Dispatcher.UIThread.InvokeAsync(() =>
@@ -44,4 +84,20 @@ internal sealed class PublicShellControlService : IPublicShellControlService
             Source: "PublicIpc",
             Reason: "External IPC requested exit.")) == true);
     }
+
+    private static PublicShellStatus CreateUnavailableStatus()
+    {
+        return new PublicShellStatus(
+            Environment.ProcessId,
+            DateTimeOffset.UtcNow,
+            "unknown",
+            "Unavailable",
+            false,
+            false,
+            false,
+            false,
+            false,
+            new PublicTrayStatus("Unavailable", false, false, false, false, 0),
+            new PublicTaskbarStatus(false, false, false, false, false, false));
+    }
 }

LanMountainDesktop/ViewModels/SettingsViewModels.cs

@@ -13,6 +13,7 @@ using LanMountainDesktop.PluginSdk;
 using LanMountainDesktop.Services;
 using LanMountainDesktop.Services.Settings;
 using LanMountainDesktop.Settings.Core;
+using LanMountainDesktop.Shared.Contracts.Launcher;
 
 namespace LanMountainDesktop.ViewModels;
 
@@ -201,7 +202,7 @@ public sealed partial class GeneralSettingsPageViewModel : ViewModelBase, IDispo
         SelectedRenderMode = RenderModes.FirstOrDefault(option =>
             string.Equals(option.Value, normalizedRenderMode, StringComparison.OrdinalIgnoreCase))
             ?? RenderModes[0];
-        EnableSlideTransition = appSnapshot.EnableSlideTransition;
+        ApplyTransitionPreferences(appSnapshot.EnableFadeTransition, appSnapshot.EnableSlideTransition);
         ShowInTaskbar = appSnapshot.ShowInTaskbar;
         _isInitializing = false;
 
@@ -235,9 +236,11 @@ public sealed partial class GeneralSettingsPageViewModel : ViewModelBase, IDispo
             return;
         }
 
-        if (changedKeys.Contains(nameof(AppSettingsSnapshot.EnableSlideTransition)))
+        if (changedKeys.Contains(nameof(AppSettingsSnapshot.EnableSlideTransition)) ||
+            changedKeys.Contains(nameof(AppSettingsSnapshot.EnableFadeTransition)))
         {
-            EnableSlideTransition = _settingsFacade.Settings.LoadSnapshot<AppSettingsSnapshot>(SettingsScope.App).EnableSlideTransition;
+            var snapshot = _settingsFacade.Settings.LoadSnapshot<AppSettingsSnapshot>(SettingsScope.App);
+            ApplyTransitionPreferences(snapshot.EnableFadeTransition, snapshot.EnableSlideTransition);
         }
 
         if (changedKeys.Contains(nameof(AppSettingsSnapshot.ShowInTaskbar)))
@@ -263,6 +266,9 @@ public sealed partial class GeneralSettingsPageViewModel : ViewModelBase, IDispo
     [ObservableProperty]
     private SelectionOption _selectedRenderMode = new(AppRenderingModeHelper.Default, "Default");
 
+    [ObservableProperty]
+    private bool _enableFadeTransition = true;
+
     [ObservableProperty]
     private bool _enableSlideTransition;
 
@@ -271,6 +277,12 @@ public sealed partial class GeneralSettingsPageViewModel : ViewModelBase, IDispo
 
     public bool IsSlideTransitionAvailable => System.Runtime.InteropServices.RuntimeInformation.IsOSPlatform(System.Runtime.InteropServices.OSPlatform.Windows);
 
+    public bool IsFadeTransitionToggleEnabled => !EnableSlideTransition;
+
+    public string FadeTransitionDescription => EnableSlideTransition
+        ? "滑动模式已启用，淡入淡出不可同时使用。"
+        : "启用后，启动与恢复过程使用淡入淡出效果。";
+
     [ObservableProperty]
     private string _pageTitle = string.Empty;
 
@@ -372,8 +384,22 @@ public sealed partial class GeneralSettingsPageViewModel : ViewModelBase, IDispo
 
     partial void OnEnableSlideTransitionChanged(bool value)
     {
-        if (_isInitializing) return;
-        SaveField(nameof(AppSettingsSnapshot.EnableSlideTransition), value);
+        if (_isInitializing)
+        {
+            return;
+        }
+
+        SaveTransitionPreferences(EnableFadeTransition, value);
+    }
+
+    partial void OnEnableFadeTransitionChanged(bool value)
+    {
+        if (_isInitializing)
+        {
+            return;
+        }
+
+        SaveTransitionPreferences(value, EnableSlideTransition);
     }
 
     partial void OnShowInTaskbarChanged(bool value)
@@ -394,6 +420,35 @@ public sealed partial class GeneralSettingsPageViewModel : ViewModelBase, IDispo
         _settingsFacade.Settings.SaveSnapshot(SettingsScope.App, snapshot, changedKeys: [key]);
     }
 
+    private void SaveTransitionPreferences(bool enableFadeTransition, bool enableSlideTransition)
+    {
+        var normalized = StartupVisualPreferencesResolver.FromFlags(enableFadeTransition, enableSlideTransition);
+        var snapshot = _settingsFacade.Settings.LoadSnapshot<AppSettingsSnapshot>(SettingsScope.App);
+        snapshot.EnableFadeTransition = normalized.EnableFadeTransition;
+        snapshot.EnableSlideTransition = normalized.EnableSlideTransition;
+        ApplyTransitionPreferences(normalized.EnableFadeTransition, normalized.EnableSlideTransition);
+        _settingsFacade.Settings.SaveSnapshot(
+            SettingsScope.App,
+            snapshot,
+            changedKeys:
+            [
+                nameof(AppSettingsSnapshot.EnableFadeTransition),
+                nameof(AppSettingsSnapshot.EnableSlideTransition)
+            ]);
+    }
+
+    private void ApplyTransitionPreferences(bool enableFadeTransition, bool enableSlideTransition)
+    {
+        var normalized = StartupVisualPreferencesResolver.FromFlags(enableFadeTransition, enableSlideTransition);
+        var wasInitializing = _isInitializing;
+        _isInitializing = true;
+        EnableFadeTransition = normalized.EnableFadeTransition;
+        EnableSlideTransition = normalized.EnableSlideTransition;
+        _isInitializing = wasInitializing;
+        OnPropertyChanged(nameof(IsFadeTransitionToggleEnabled));
+        OnPropertyChanged(nameof(FadeTransitionDescription));
+    }
+
     private IReadOnlyList<SelectionOption> CreateLanguageOptions()
     {
         return

LanMountainDesktop/Views/MainWindow.SettingsHardCut.Stubs.cs

@@ -79,6 +79,7 @@ public partial class MainWindow
                 string.Equals(key, nameof(AppSettingsSnapshot.UpdateDownloadSource), StringComparison.OrdinalIgnoreCase) ||
                 string.Equals(key, nameof(AppSettingsSnapshot.UpdateDownloadThreads), StringComparison.OrdinalIgnoreCase) ||
                 string.Equals(key, nameof(AppSettingsSnapshot.EnableThreeFingerSwipe), StringComparison.OrdinalIgnoreCase) ||
+                string.Equals(key, nameof(AppSettingsSnapshot.EnableFadeTransition), StringComparison.OrdinalIgnoreCase) ||
                 string.Equals(key, nameof(AppSettingsSnapshot.ShowInTaskbar), StringComparison.OrdinalIgnoreCase) ||
                 string.Equals(key, nameof(AppSettingsSnapshot.EnableSlideTransition), StringComparison.OrdinalIgnoreCase)))
             {
@@ -690,6 +691,7 @@ public partial class MainWindow
             StatusBarShadowColor = _statusBarShadowColor,
             StatusBarShadowOpacity = _statusBarShadowOpacity,
             EnableThreeFingerSwipe = existingSnapshot.EnableThreeFingerSwipe,
+            EnableFadeTransition = existingSnapshot.EnableFadeTransition,
             EnableSlideTransition = existingSnapshot.EnableSlideTransition,
             ShowInTaskbar = existingSnapshot.ShowInTaskbar,
             EnableFusedDesktop = existingSnapshot.EnableFusedDesktop,

LanMountainDesktop/Views/MainWindow.axaml.cs

@@ -1,5 +1,6 @@
 using System;
 using System.Collections.Generic;
+using System.Diagnostics;
 using System.IO;
 using System.Linq;
 using System.Runtime.InteropServices;
@@ -23,6 +24,7 @@ using LanMountainDesktop.Models;
 using LanMountainDesktop.PluginSdk;
 using LanMountainDesktop.Services;
 using LanMountainDesktop.Services.Settings;
+using LanMountainDesktop.Shared.Contracts.Launcher;
 using LanMountainDesktop.Theme;
 using LanMountainDesktop.Views.Components;
 
@@ -134,6 +136,8 @@ public partial class MainWindow : Window
     private string _gridSpacingPreset = "Relaxed";
     private bool _isSlideAnimationActive;
     private TranslateTransform? _desktopPageSlideTransform;
+    private PixelPoint? _preparedWindowTargetPosition;
+    private PixelPoint? _preparedWindowHiddenPosition;
     private string _statusBarSpacingMode = "Relaxed";
     private int _statusBarCustomSpacingPercent = 12;
     private bool _statusBarClockTransparentBackground;
@@ -862,24 +866,45 @@ public partial class MainWindow : Window
         return _desktopPageSlideTransform;
     }
 
+    internal bool ShouldUseFullscreenWindow()
+    {
+        return GetStartupVisualPreferences().Mode != StartupVisualMode.SlideSplash;
+    }
+
+    internal void EnsureForegroundWindowLayout()
+    {
+        if (!IsSlideTransitionEnabled())
+        {
+            return;
+        }
+
+        var layout = ResolveWindowAnimationLayout();
+        ApplyWindowAnimationLayout(layout);
+        Position = layout.VisiblePosition;
+    }
+
     private async void SlideOutAndMinimizeAsync()
     {
         _isSlideAnimationActive = true;
         DesktopPage.IsHitTestVisible = false;
 
-        var useSlide = IsSlideTransitionEnabled();
-        var slideTransform = GetDesktopPageSlideTransform();
+        var preferences = GetStartupVisualPreferences();
+        WindowAnimationLayout? slideLayout = null;
 
-        if (useSlide)
+        if (preferences.Mode == StartupVisualMode.SlideSplash)
         {
-            slideTransform.X = Bounds.Width;
+            slideLayout = ResolveWindowAnimationLayout();
+            ApplyWindowAnimationLayout(slideLayout.Value);
+            await AnimateWindowPositionAsync(
+                Position,
+                slideLayout.Value.HiddenPosition,
+                FluttermotionToken.Intro).ConfigureAwait(false);
+        }
+        else if (preferences.Mode == StartupVisualMode.Fade)
+        {
+            DesktopPage.Opacity = 0;
+            await Task.Delay(FluttermotionToken.Page);
         }
-
-        DesktopPage.Opacity = 0;
-
-        await Task.Delay(useSlide
-            ? FluttermotionToken.Intro
-            : FluttermotionToken.Page);
 
         if (!_isSlideAnimationActive)
         {
@@ -900,44 +925,63 @@ public partial class MainWindow : Window
             WindowState = WindowState.Minimized;
         }
 
-        slideTransform.X = 0;
         DesktopPage.Opacity = 1;
         DesktopPage.IsHitTestVisible = true;
         _isSlideAnimationActive = false;
+        if (slideLayout is { } layout)
+        {
+            Position = layout.VisiblePosition;
+        }
     }
 
     public void PrepareEnterAnimation()
     {
         _isSlideAnimationActive = false;
 
-        var useSlide = IsSlideTransitionEnabled();
-        var slideTransform = GetDesktopPageSlideTransform();
+        var preferences = GetStartupVisualPreferences();
+        _preparedWindowTargetPosition = null;
+        _preparedWindowHiddenPosition = null;
 
-        var savedTransitions = DesktopPage.Transitions;
-        DesktopPage.Transitions = null;
-
-        DesktopPage.Opacity = 0;
-
-        if (useSlide)
+        if (preferences.Mode == StartupVisualMode.SlideSplash)
         {
-            var screen = Screens.ScreenFromVisual(this);
-            var scale = screen?.Scaling ?? 1d;
-            var screenWidthDip = screen is null
-                ? 1920d
-                : screen.WorkingArea.Width / Math.Max(scale, 0.01d);
-            slideTransform.X = Bounds.Width > 0 ? Bounds.Width : screenWidthDip;
+            var layout = ResolveWindowAnimationLayout();
+            _preparedWindowTargetPosition = layout.VisiblePosition;
+            _preparedWindowHiddenPosition = layout.HiddenPosition;
+            ApplyWindowAnimationLayout(layout);
+            Position = layout.HiddenPosition;
+            DesktopPage.Opacity = 1;
+            DesktopPage.IsHitTestVisible = false;
+            _isSlideAnimationActive = true;
+            return;
         }
 
-        DesktopPage.Transitions = savedTransitions;
-        DesktopPage.IsHitTestVisible = false;
-        _isSlideAnimationActive = true;
+        if (preferences.Mode == StartupVisualMode.Fade)
+        {
+            var savedTransitions = DesktopPage.Transitions;
+            DesktopPage.Transitions = null;
+            DesktopPage.Opacity = 0;
+            DesktopPage.Transitions = savedTransitions;
+            DesktopPage.IsHitTestVisible = false;
+            _isSlideAnimationActive = true;
+            return;
+        }
+
+        DesktopPage.Opacity = 1;
+        DesktopPage.IsHitTestVisible = true;
     }
 
     public void PlayEnterAnimation()
     {
-        var slideTransform = GetDesktopPageSlideTransform();
+        var preferences = GetStartupVisualPreferences();
+        if (preferences.Mode == StartupVisualMode.SlideSplash &&
+            _preparedWindowTargetPosition is { } targetPosition &&
+            _preparedWindowHiddenPosition is { } hiddenPosition)
+        {
+            _ = PlayWindowEnterAnimationAsync(hiddenPosition, targetPosition);
+            return;
+        }
+
         DesktopPage.Opacity = 1;
-        slideTransform.X = 0;
         DesktopPage.IsHitTestVisible = true;
         _isSlideAnimationActive = false;
     }
@@ -949,10 +993,67 @@ public partial class MainWindow : Window
             return false;
         }
 
-        var snapshot = _settingsService.LoadSnapshot<AppSettingsSnapshot>(SettingsScope.App);
-        return snapshot.EnableSlideTransition;
+        return GetStartupVisualPreferences().Mode == StartupVisualMode.SlideSplash;
     }
 
+    private StartupVisualPreferences GetStartupVisualPreferences()
+    {
+        var snapshot = _settingsService.LoadSnapshot<AppSettingsSnapshot>(SettingsScope.App);
+        return StartupVisualPreferencesResolver.FromFlags(
+            snapshot.EnableFadeTransition,
+            snapshot.EnableSlideTransition);
+    }
+
+    private WindowAnimationLayout ResolveWindowAnimationLayout()
+    {
+        var screen = Screens.ScreenFromVisual(this) ?? Screens.Primary ?? Screens.All.FirstOrDefault();
+        var workingArea = screen?.WorkingArea ?? new PixelRect(0, 0, 1920, 1080);
+        var scaling = Math.Max(screen?.Scaling ?? 1d, 0.01d);
+
+        return new WindowAnimationLayout(
+            new PixelPoint(workingArea.X, workingArea.Y),
+            new PixelPoint(workingArea.X + workingArea.Width, workingArea.Y),
+            new Size(workingArea.Width / scaling, workingArea.Height / scaling));
+    }
+
+    private void ApplyWindowAnimationLayout(WindowAnimationLayout layout)
+    {
+        WindowState = WindowState.Normal;
+        Width = layout.WindowSize.Width;
+        Height = layout.WindowSize.Height;
+    }
+
+    private async Task PlayWindowEnterAnimationAsync(PixelPoint hiddenPosition, PixelPoint targetPosition)
+    {
+        Position = hiddenPosition;
+        await AnimateWindowPositionAsync(hiddenPosition, targetPosition, FluttermotionToken.Intro);
+        DesktopPage.IsHitTestVisible = true;
+        _isSlideAnimationActive = false;
+    }
+
+    private async Task AnimateWindowPositionAsync(PixelPoint from, PixelPoint to, TimeSpan duration)
+    {
+        var totalMilliseconds = Math.Max(duration.TotalMilliseconds, 1d);
+        var stopwatch = Stopwatch.StartNew();
+
+        while (stopwatch.Elapsed < duration)
+        {
+            var progress = Math.Clamp(stopwatch.Elapsed.TotalMilliseconds / totalMilliseconds, 0d, 1d);
+            var eased = 1d - Math.Pow(1d - progress, 3d);
+            var x = (int)Math.Round(from.X + ((to.X - from.X) * eased));
+            var y = (int)Math.Round(from.Y + ((to.Y - from.Y) * eased));
+            Position = new PixelPoint(x, y);
+            await Task.Delay(16).ConfigureAwait(false);
+        }
+
+        Position = to;
+    }
+
+    private readonly record struct WindowAnimationLayout(
+        PixelPoint VisiblePosition,
+        PixelPoint HiddenPosition,
+        Size WindowSize);
+
     private void OnWindowPropertyChanged(object? sender, AvaloniaPropertyChangedEventArgs e)
     {
         if (e.Property != WindowStateProperty)
@@ -966,10 +1067,17 @@ public partial class MainWindow : Window
         if (oldState == WindowState.Minimized && newState != WindowState.Minimized)
         {
             PrepareEnterAnimation();
-            
-            if (newState != WindowState.FullScreen)
+
+            if (ShouldUseFullscreenWindow())
             {
-                WindowState = WindowState.FullScreen;
+                if (newState != WindowState.FullScreen)
+                {
+                    WindowState = WindowState.FullScreen;
+                }
+            }
+            else if (newState == WindowState.Minimized)
+            {
+                WindowState = WindowState.Normal;
             }
 
             Dispatcher.UIThread.Post(() =>
@@ -980,7 +1088,8 @@ public partial class MainWindow : Window
             return;
         }
 
-        if (newState is WindowState.Minimized or WindowState.FullScreen)
+        if (newState == WindowState.Minimized ||
+            (ShouldUseFullscreenWindow() && newState == WindowState.FullScreen))
         {
             return;
         }
@@ -999,7 +1108,10 @@ public partial class MainWindow : Window
 
             if (WindowState is not (WindowState.Minimized or WindowState.FullScreen))
             {
-                WindowState = WindowState.FullScreen;
+                if (ShouldUseFullscreenWindow())
+                {
+                    WindowState = WindowState.FullScreen;
+                }
             }
         });
     }

LanMountainDesktop/Views/SettingsPages/GeneralSettingsPage.axaml

@@ -9,7 +9,6 @@
     <ScrollViewer VerticalScrollBarVisibility="Auto">
         <StackPanel Classes="settings-page-container settings-page-animated">
 
-            <!-- 区域设置分组 -->
             <controls:IconText Icon="Globe"
                                Text="{Binding BasicHeader}"
                                Margin="0,0,0,4" />
@@ -76,7 +75,6 @@
 
             <Separator Classes="settings-separator" />
 
-            <!-- 运行时设置分组 -->
             <controls:IconText Icon="DeveloperBoard"
                                Text="{Binding RuntimeHeader}"
                                Margin="0,0,0,4" />
@@ -106,8 +104,20 @@
                 </ui:SettingsExpanderItem>
             </ui:SettingsExpander>
 
-            <ui:SettingsExpander Header="滑入滑出过渡效果"
-                                 Description="启用后，进入和退出桌面时使用滑入滑出动画（仅 Windows）"
+            <ui:SettingsExpander Header="淡入淡出效果"
+                                 Description="{Binding FadeTransitionDescription}"
+                                 IsVisible="{Binding IsSlideTransitionAvailable}">
+                <ui:SettingsExpander.IconSource>
+                    <fi:SymbolIconSource Symbol="ArrowUpload" />
+                </ui:SettingsExpander.IconSource>
+                <ui:SettingsExpander.Footer>
+                    <ToggleSwitch IsChecked="{Binding EnableFadeTransition}"
+                                  IsEnabled="{Binding IsFadeTransitionToggleEnabled}" />
+                </ui:SettingsExpander.Footer>
+            </ui:SettingsExpander>
+
+            <ui:SettingsExpander Header="启动滑入滑出效果"
+                                 Description="启用后，启动和恢复时从屏幕右侧边缘滑入或滑出，仅 Windows 可用。"
                                  IsVisible="{Binding IsSlideTransitionAvailable}">
                 <ui:SettingsExpander.IconSource>
                     <fi:SymbolIconSource Symbol="ArrowRight" />
@@ -118,7 +128,7 @@
             </ui:SettingsExpander>
 
             <ui:SettingsExpander Header="桌面主窗口在任务栏显示图标"
-                                 Description="仅控制桌面主窗口在系统任务栏中的图标显示；不会影响设置窗口，设置窗口打开时始终保留独立任务栏图标">
+                                 Description="仅控制桌面主窗口在系统任务栏中的图标显示，不影响设置窗口。">
                 <ui:SettingsExpander.IconSource>
                     <fi:SymbolIconSource Symbol="Window" />
                 </ui:SettingsExpander.IconSource>

docs/EXTERNAL_IPC_ARCHITECTURE.md

@@ -40,7 +40,7 @@ Current built-in `[IpcPublic]` contracts:
 - `IPublicAppInfoService`
   - Returns application metadata such as version, codename, process id, pipe name, and startup time.
 - `IPublicShellControlService`
-  - Allows external .NET clients to activate the shell, open settings, request restart, and request exit.
+  - Allows external .NET clients to query shell status, activate the shell, repair tray readiness, repair taskbar entry visibility, open settings, request restart, and request exit.
 - `IPublicPluginCatalogService`
   - Returns the merged public IPC catalog snapshot exposed by Host.
 
@@ -77,6 +77,8 @@ Launcher no longer depends on the previous custom named-pipe length-prefixed pro
 
 This means Splash/OOBE is now just another IPC consumer on the same base transport used by external integrators.
 
+Launcher-to-launcher de-duplication is intentionally separate from Host Public IPC. The active Launcher coordinator uses a per-user local pipe and `startup-attempt.json` heartbeat so secondary Launchers attach to the coordinator before any host process can be started twice.
+
 ## Plugin Public IPC Contribution Model
 
 Plugins can contribute new external IPC services in two ways:

docs/LAUNCHER.md

@@ -569,3 +569,7 @@ Launcher now consumes Host startup telemetry from the unified public IPC stack:
 - Launcher connects through `LanMountainDesktopIpcClient`
 
 The previous custom length-prefixed named-pipe transport is no longer the primary startup communication path.
+
+## Coordinator Guard
+
+Launcher also owns a small per-user local coordinator used only between Launcher processes. It reserves `startup-attempt.json` before host launch, publishes a heartbeat, and exposes a local coordinator pipe for secondary Launchers. A secondary Launcher must attach to that coordinator or activate the existing Host through Public IPC instead of starting another Host process. See [Launcher Coordinator](LAUNCHER_COORDINATOR.md).

docs/LAUNCHER_COORDINATOR.md

@@ -0,0 +1,31 @@
+# Launcher Coordinator
+
+LanMountainDesktop Launcher uses a per-user coordinator to prevent duplicate host startup.
+
+## Rules
+
+- A Launcher reserves `%LocalAppData%\LanMountainDesktop\.launcher\state\startup-attempt.json` before starting the host.
+- The active record stores coordinator pid, coordinator pipe name, heartbeat, host pid, Public IPC state, and shell status.
+- Only the active coordinator may start the host process.
+- Secondary Launchers attach to the coordinator and request desktop activation.
+- A coordinator is considered live while its pid exists and its heartbeat is newer than `10s`.
+- Normal launch probes Host Public IPC first; if the host is already running, Launcher activates it and exits.
+
+## Tray And Taskbar
+
+- Tray icon and tray menu are mandatory and are not controlled by user settings.
+- Tray watchdog starts with the shell and runs until process exit.
+- `ShowInTaskbar=true` affects only the main-window taskbar entry.
+- When `ShowInTaskbar=true`, background mode uses a minimized taskbar entry while keeping tray visible.
+- Pure `TrayOnly` is allowed only when `ShowInTaskbar=false` and tray is ready.
+
+## Public Shell IPC
+
+Launcher and external callers can use:
+
+- `GetShellStatusAsync()`
+- `ActivateMainWindowWithStatusAsync()`
+- `EnsureTrayReadyAsync()`
+- `EnsureTaskbarEntryAsync()`
+
+These APIs report process, shell, tray, taskbar, and activation state separately so callers do not infer health from window visibility alone.

docs/LAUNCHER_STARTUP_VISUALS.md

@@ -0,0 +1,28 @@
+# Launcher Startup Visuals
+
+This supplement records the startup rules that are shared by the launcher and the desktop host.
+
+## Timeout behavior
+
+- `30 seconds` is a soft timeout.
+- Soft timeout means `still starting`, not `failed`.
+- When the host process is alive or Public IPC is connected, Launcher keeps waiting and avoids launching another host process.
+- `120 seconds` is the hard timeout for `desktop_not_visible`.
+
+## Visual mode resolution
+
+- `EnableSlideTransition = true` resolves to `SlideSplash` and forces `EnableFadeTransition = false`.
+- `EnableSlideTransition = false` and `EnableFadeTransition = false` resolves to `StaticSplash`.
+- `EnableSlideTransition = false` and `EnableFadeTransition = true` resolves to `Fade`.
+
+## Fullscreen splash rules
+
+- Fullscreen splash uses the shared `logo_nightly.png` asset.
+- Slide splash enters from the right edge of the target screen and exits back to the right edge.
+- Static splash uses the same fullscreen black surface without motion.
+
+## Recovery rules
+
+- Closing Launcher during startup does not cancel the startup attempt.
+- Relaunching Launcher attaches to the active attempt instead of spawning a second desktop process.
+- If a host process is still alive during failure handling, Launcher offers activation or continued waiting before any retry.