Fix audio player: use explicit platform-specific imports and dynamic typing

b0esche_cloud/lib/widgets/audio_player_bar.dart

@@ -6,8 +6,8 @@ import '../theme/app_theme.dart';
 import '../theme/modern_glass_button.dart';
 
 // Conditional imports for audio
-import 'package:just_audio/just_audio.dart'
-    if (dart.library.html) 'web_audio_player.dart';
+import 'package:just_audio/just_audio.dart' as just_audio;
+import 'web_audio_player.dart' as web_audio;
 
 class AudioPlayerBar extends StatefulWidget {
   final String fileName;
@@ -29,7 +29,7 @@ class AudioPlayerBar extends StatefulWidget {
 
 class _AudioPlayerBarState extends State<AudioPlayerBar>
     with SingleTickerProviderStateMixin {
-  late AudioPlayer _audioPlayer;
+  dynamic _audioPlayer;
   late AnimationController _iconController;
   Duration _duration = Duration.zero;
   Duration _position = Duration.zero;
@@ -43,7 +43,7 @@ class _AudioPlayerBarState extends State<AudioPlayerBar>
   @override
   void initState() {
     super.initState();
-    _audioPlayer = AudioPlayer();
+    _audioPlayer = kIsWeb ? web_audio.AudioPlayer() : just_audio.AudioPlayer();
     _iconController = AnimationController(
       vsync: this,
       duration: const Duration(milliseconds: 250),
@@ -67,7 +67,7 @@ class _AudioPlayerBarState extends State<AudioPlayerBar>
     try {
       if (kIsWeb) {
         // Web implementation
-        await (_audioPlayer as dynamic).setUrl(
+        await _audioPlayer.setUrl(
           widget.fileUrl,
           mimeType: widget.mimeType,
         );
@@ -109,10 +109,7 @@ class _AudioPlayerBarState extends State<AudioPlayerBar>
       } else {
         // Mobile implementation (just_audio)
         await _audioPlayer.setAudioSource(
-          // ignore: undefined_method
-          AudioSource.uri(
-            Uri.parse(widget.fileUrl),
-          ), // ignore: undefined_getter
+          just_audio.AudioSource.uri(Uri.parse(widget.fileUrl)),
         );
         _audioPlayer.durationStream.firstWhere((d) => d != null).then((
           d,