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.
Implement startup visual behavior, de-duplicate startup attempts, and improve failure UX.
Key changes:
- Add spec and docs for startup visuals and timing contract (.trae/specs and docs/LAUNCHER_STARTUP_VISUALS.md).
- Introduce StartupVisualPreferences contract and resolver; create SplashWindow via resolved mode.
- Add StartupAttemptRecord model and a file-backed StartupAttemptRegistry to persist and coordinate in-progress startup attempts (attach/adopt, soft/hard timeouts, IPC/connect state, lifecycle updates).
- Update LauncherFlowCoordinator to: adopt/attach to existing attempts, track IPC connection and soft/hard timeouts (30s/120s), show delayed UI state, attempt foreground recovery via public IPC, compose detailed launch result metadata, and mark registry states (soft timeout, detached waiting, succeeded, failed).
- Add TryActivateExistingInstanceAsync to attempt activating an existing desktop via IPC.
- Change failure flow: ShowFailureWindowAsync now returns user choice; ErrorWindow updated to present Activate/Wait/Open Logs/Exit semantics and new layouts/styles; improved button wiring and debug/dev mode handling.
- Add UI and resource tweaks (ErrorWindow and SplashWindow changes), project asset link for nightly logo, and unit tests for StartupVisualPreferences.
These changes prevent duplicate desktop processes during slow startups, provide clearer UX for delayed startups, and persist startup attempt state across Launcher invocations for safer recovery/attach behavior.
Introduce a new LanMountainDesktop.Shared.IPC project implementing a public IPC host and client (LanMountainDesktopIpcClient, PublicIpcHostService), IPC constants and routed notify IDs, DTOs and DI helpers for registering public services. Update Plugin SDK to allow plugins to contribute public IPC services and registrations, add related descriptors/records and extension helpers. Migrate Launcher/App to use the new public IPC for startup/loading notifications and wiring (including TryConnect helper), switch LoadingStateReporter to use the external notification publisher, and add host-side public services (app info, shell control, plugin catalog). Include integration tests and spec/checklist/docs for the external IPC public API.
Introduce a per-user OOBE state model and hardened launch/elevation handling. Adds OobeStateFile/OobeLaunchDecision models, OobeStateService (persisting %LOCALAPPDATA%/.launcher/state/oobe-state.json), and LauncherExecutionContext to capture elevation and user SID. CommandContext now normalizes/infers launch-source values (normal, postinstall, apply-update, plugin-install, debug-preview) and exposes maintenance checks. LauncherFlowCoordinator propagates richer launcher context details for diagnostics and suppresses OOBE for elevated/maintenance contexts. PluginInstallerService avoids requesting elevation for user-scoped installs and returns a clear error when installation target is outside the current user's LocalAppData. LauncherClient maps and surfaces result codes, UpdateWorkflow and installer invocation now pass explicit --launch-source values, and WelcomeOobeStep persists OOBE completion via the new service. Adds unit tests (CommandContext, OobeStateService, PluginInstallerService), docs/specs/checklists for the contract, and makes internals visible to tests.
