feat: Add Audio Gallery screen and integrate into Debug Tools menu

feat: Implement audio playback controls and audio management in the gallery
refactor: Update audio engine interface to include stopAllAudio method

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

packages/wolf_3d_flutter/lib/audio/audio_adaptor.dart

@@ -17,6 +17,11 @@ class FlutterAudioAdapter implements EngineAudio {
     wolf3d.audio.stopMusic();
   }
 
+  @override
+  Future<void> stopAllAudio() async {
+    await wolf3d.audio.stopAllAudio();
+  }
+
   @override
   void playSoundEffect(int sfxId) {
     wolf3d.audio.playSoundEffect(sfxId);