Fix Title Update Manager not refreshing app list (#6507)

src/Ryujinx/UI/Windows/TitleUpdateWindow.axaml.cs

@@ -1,4 +1,6 @@
+using Avalonia;
 using Avalonia.Controls;
+using Avalonia.Controls.ApplicationLifetimes;
 using Avalonia.Interactivity;
 using Avalonia.Styling;
 using FluentAvalonia.UI.Controls;
@@ -59,9 +61,15 @@ namespace Ryujinx.Ava.UI.Windows
         {
             ViewModel.Save();
 
-            if (VisualRoot is MainWindow window)
+            if (Application.Current?.ApplicationLifetime is IClassicDesktopStyleApplicationLifetime al)
             {
-                window.LoadApplications();
+                foreach (Window window in al.Windows)
+                {
+                    if (window is MainWindow mainWindow)
+                    {
+                        mainWindow.LoadApplications();
+                    }
+                }
             }
 
             ((ContentDialog)Parent).Hide();