feat: Implement Playlists and Programs Management

- Added PlaylistsGroupViewModel to manage playlists and selection.
- Introduced ProgramsGroupViewModel for handling program groups and subscriptions.
- Created ProgramsListViewModel to manage individual program listings.
- Developed SettingsViewModel for user settings including playlist management.
- Implemented TVPlayerViewModel as the main view model coordinating screens and data.
- Added PlayerView for video playback with LibVLC integration.
- Created XAML views for PlaylistsGroup, ProgramsGroup, ProgramsList, and Settings.
- Added sample M3U playlist for testing.
- Documented WPF build instructions and project structure in WPF-BUILD.md.
- Configured global.json for .NET SDK versioning.

TV Player Avalonia/Views/ProgramsListView.axaml.cs

@@ -0,0 +1,12 @@
+using Avalonia.Controls;
+using Avalonia.Markup.Xaml;
+
+namespace TV_Player.AvaloniaApp.Views;
+
+public partial class ProgramsListView : UserControl
+{
+    public ProgramsListView()
+    {
+        AvaloniaXamlLoader.Load(this);
+    }
+}