Polish AmiReel UI and improve render workflow

AmiReel.WinUI/App.xaml.cs

@@ -0,0 +1,47 @@
+using Windows.ApplicationModel;
+using Windows.ApplicationModel.Activation;
+using Windows.Foundation;
+using Windows.Foundation.Collections;
+using Microsoft.UI.Xaml;
+using Microsoft.UI.Xaml.Controls;
+using Microsoft.UI.Xaml.Controls.Primitives;
+using Microsoft.UI.Xaml.Data;
+using Microsoft.UI.Xaml.Input;
+using Microsoft.UI.Xaml.Media;
+using Microsoft.UI.Xaml.Navigation;
+using Microsoft.UI.Xaml.Shapes;
+using WinRT.Interop;
+
+// To learn more about WinUI, the WinUI project structure,
+// and more about our project templates, see: http://aka.ms/winui-project-info.
+
+namespace AmiReel_WinUI;
+
+/// <summary>
+/// Provides application-specific behavior to supplement the default Application class.
+/// </summary>
+public partial class App : Application
+{
+    private Window? _window;
+    public static IntPtr MainWindowHandle { get; private set; }
+    
+    /// <summary>
+    /// Initializes the singleton application object.  This is the first line of authored code
+    /// executed, and as such is the logical equivalent of main() or WinMain().
+    /// </summary>
+    public App()
+    {
+        InitializeComponent();
+    }
+
+    /// <summary>
+    /// Invoked when the application is launched.
+    /// </summary>
+    /// <param name="args">Details about the launch request and process.</param>
+    protected override void OnLaunched(Microsoft.UI.Xaml.LaunchActivatedEventArgs args)
+    {
+        _window = new MainWindow();
+        MainWindowHandle = WindowNative.GetWindowHandle(_window);
+        _window.Activate();
+    }
+}