Refactor audio module to use built-in music and sound effect identifiers

- Introduced BuiltInMusicModule and BuiltInSfxModule to replace RetailMusicModule and RetailSfxModule.
- Updated RetailAssetRegistry and SharewareAssetRegistry to utilize the new built-in modules.
- Removed deprecated MusicKey and SfxKey classes, replacing them with Music and SoundEffect enums for better clarity and maintainability.
- Adjusted music and sound effect resolution methods to align with the new structure.
- Updated audio playback methods in WolfAudio and FlutterAudioAdapter to accept the new Music and SoundEffect types.
- Refactored tests to accommodate changes in audio event handling and ensure compatibility with the new identifiers.

Signed-off-by: Hans Kokx <hans.d.kokx@gmail.com>

packages/wolf_3d_flutter/lib/audio/audio_adaptor.dart

@@ -8,8 +8,8 @@ class FlutterAudioAdapter implements EngineAudio {
   FlutterAudioAdapter(this.wolf3d);
 
   @override
-  void playLevelMusic(WolfLevel level) {
-    wolf3d.audio.playLevelMusic(level);
+  void playLevelMusic(Music music) {
+    wolf3d.audio.playLevelMusic(music);
   }
 
   @override
@@ -23,8 +23,13 @@ class FlutterAudioAdapter implements EngineAudio {
   }
 
   @override
-  void playSoundEffect(int sfxId) {
-    wolf3d.audio.playSoundEffect(sfxId);
+  void playSoundEffect(SoundEffect effect) {
+    wolf3d.audio.playSoundEffect(effect);
+  }
+
+  @override
+  void playSoundEffectId(int sfxId) {
+    wolf3d.audio.playSoundEffectId(sfxId);
   }
 
   @override