Enhance media player with artwork display support (#2108)

Added a new using directive for Android.Graphics.Drawables in MediaManager.android.cs. Enhanced the StartService method by:
- Adding a null check for PlayerView.
- Setting ArtworkDisplayMode to StyledPlayerView.ArtworkDisplayModeFit.
- Fetching and setting artwork from a URL as DefaultArtwork.

src/CommunityToolkit.Maui.MediaElement/Views/MediaManager.android.cs

@@ -1,6 +1,7 @@
 using System.Diagnostics.CodeAnalysis;
 using Android.Content;
 using Android.Graphics;
+using Android.Graphics.Drawables;
 using Android.OS;
 using Android.Support.V4.Media;
 using Android.Support.V4.Media.Session;
@@ -659,7 +660,14 @@ async Task StartService(CancellationToken cancellationToken = default)
 			await checkPermissionsTask.WaitAsync(cancellationToken);
 		}
 
+		ArgumentNullException.ThrowIfNull(PlayerView);
+		PlayerView.ArtworkDisplayMode = StyledPlayerView.ArtworkDisplayModeFit;
+		Android.Content.Context? context = Platform.AppContext;
+		Android.Content.Res.Resources? resources = context.Resources;
+
 		var bitmap = await GetBitmapFromUrl(MediaElement.MetadataArtworkUrl, cancellationToken);
+		PlayerView.DefaultArtwork = new BitmapDrawable(resources, bitmap);
+
 		var mediaMetadata = new MediaMetadataCompat.Builder();
 		mediaMetadata.PutString(MediaMetadataCompat.MetadataKeyArtist, MediaElement.MetadataArtist);
 		mediaMetadata.PutString(MediaMetadataCompat.MetadataKeyTitle, MediaElement.MetadataTitle);