Load menu and level audio dynamically

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

lib/features/renderer/renderer.dart

@@ -69,11 +69,15 @@ class _WolfRendererState extends State<WolfRenderer>
     // Grab the specific level from the singleton
     _currentLevel = Wolf3d.I.levels[mapIndex];
 
+    // Play the exact track id Software intended for this level!
+    Wolf3d.I.audio.playLevelMusic(_currentLevel);
+
     // TODO: Initialize player position, spawn enemies based on difficulty, etc.
     debugPrint("Loaded Level: ${_currentLevel.name}");
   }
 
   void _onLevelCompleted() {
+    Wolf3d.I.audio.stopMusic();
     // When the player hits the elevator switch, advance the map
     setState(() {
       _currentMapIndex++;

lib/features/screens/episode_screen.dart

@@ -22,16 +22,13 @@ class _EpisodeScreenState extends State<EpisodeScreen> {
   @override
   void initState() {
     super.initState();
-    if (Wolf3d.I.music.isNotEmpty) {
-      Wolf3d.I.audio.playMusic(Wolf3d.I.music.first);
-    }
+    Wolf3d.I.audio.playMenuMusic();
   }
 
   void _selectEpisode(int index) {
     Wolf3d.I.setActiveEpisode(index);
     Navigator.of(context).push(
       MaterialPageRoute(
-        // We pass the audio handles so the next screen can stop them when the game starts
         builder: (context) => DifficultyScreen(),
       ),
     );
@@ -39,7 +36,6 @@ class _EpisodeScreenState extends State<EpisodeScreen> {
 
   @override
   Widget build(BuildContext context) {
-    // Determine how many episodes are available (10 levels per episode)
     final int numberOfEpisodes = (Wolf3d.I.levels.length / 10).floor().clamp(
       1,
       6,