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

LanMountainDesktop.Mobile.Android/MobileAndroidApplication.cs

@@ -0,0 +1,26 @@
+using Android.App;
+using Android.Runtime;
+using Avalonia;
+using Avalonia.Android;
+using LanMountainDesktop.Mobile;
+
+namespace LanMountainDesktop.Mobile.Android;
+
+/// <summary>
+/// Android 应用级入口。Avalonia 12 中 AppBuilder 的创建/定制由
+/// AvaloniaAndroidApplication&lt;TApp&gt; 子类负责（而非 Activity）。
+/// </summary>
+[Application]
+public class MobileAndroidApplication : AvaloniaAndroidApplication<MobileApp>
+{
+    protected MobileAndroidApplication(nint javaReference, JniHandleOwnership transfer)
+        : base(javaReference, transfer)
+    {
+    }
+
+    protected override AppBuilder CustomizeAppBuilder(AppBuilder builder)
+    {
+        return base.CustomizeAppBuilder(builder)
+            .WithInterFont();
+    }
+}