chore: cleanup unused code and dead imports

lib/main.dart

@@ -12,11 +12,9 @@ import 'package:spotiflac_android/services/cover_cache_manager.dart';
 void main() async {
   WidgetsFlutterBinding.ensureInitialized();
   
-  // Initialize services - CoverCacheManager MUST complete before app starts
   await CoverCacheManager.initialize();
   debugPrint('CoverCacheManager initialized: ${CoverCacheManager.isInitialized}');
   
-  // These can run in parallel
   await Future.wait([
     NotificationService().initialize(),
     ShareIntentService().initialize(),