Add MAUI project

src/Backend/DiunaBI.UI.Mobile/Platforms/Windows/App.xaml.cs

@@ -0,0 +1,23 @@
+using Microsoft.UI.Xaml;
+
+// To learn more about WinUI, the WinUI project structure,
+// and more about our project templates, see: http://aka.ms/winui-project-info.
+
+namespace DiunaBI.UI.Mobile.WinUI;
+
+/// <summary>
+/// Provides application-specific behavior to supplement the default Application class.
+/// </summary>
+public partial class App : MauiWinUIApplication
+{
+    /// <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()
+    {
+        this.InitializeComponent();
+    }
+
+    protected override MauiApp CreateMauiApp() => MauiProgram.CreateMauiApp();
+}