feat: 新增 Android 移动端 head 与共享移动壳（组件面板）

LanMountainDesktop.Mobile/MobileApp.axaml.cs

@@ -0,0 +1,33 @@
+using Avalonia;
+using Avalonia.Controls.ApplicationLifetimes;
+using Avalonia.Markup.Xaml;
+using LanMountainDesktop.Mobile.ViewModels;
+using LanMountainDesktop.Mobile.Views;
+
+namespace LanMountainDesktop.Mobile;
+
+/// <summary>
+/// 移动端应用入口。以单视图生命周期承载组件面板。
+/// 与桌面宿主 (LanMountainDesktop.App) 共享契约、外观与组件运行时，
+/// 但不包含桌面层、托盘、进程外插件等桌面专属能力。
+/// </summary>
+public partial class MobileApp : Application
+{
+    public override void Initialize()
+    {
+        AvaloniaXamlLoader.Load(this);
+    }
+
+    public override void OnFrameworkInitializationCompleted()
+    {
+        if (ApplicationLifetime is ISingleViewApplicationLifetime singleView)
+        {
+            singleView.MainView = new WidgetPanelView
+            {
+                DataContext = new WidgetPanelViewModel()
+            };
+        }
+
+        base.OnFrameworkInitializationCompleted();
+    }
+}