ServiceRegistry class

Dependency Injection Container for managing service lifecycle

Features:

• Singleton pattern - one instance per application
• Platform-aware service selection (web vs mobile)
• Lazy initialization of services
• Constructor injection for testability
• Clear separation of concerns

Platform Support:

• Mobile: Uses dart:io-based services (PlatformFileSystemService, BackgroundDownloaderService)
• Web: Uses URL-based services (WebFileSystemService, WebDownloadService)

Requirements:

• Mobile platforms require Flutter bindings to be initialized before ServiceRegistry (BackgroundDownloaderService uses path_provider which requires bindings)
• Call WidgetsFlutterBinding.ensureInitialized() in main() before using ServiceRegistry

Usage:

void main() {
  WidgetsFlutterBinding.ensureInitialized(); // Required for mobile
  ServiceRegistry.initialize();
  runApp(MyApp());
}

// Later in your code:
final registry = ServiceRegistry.instance;
final handlerRegistry = registry.sourceHandlerRegistry;
final handler = handlerRegistry.getHandler(source);
await handler.install(source);