LanguageSwitcherNotifier class

State notifier that manages locale switching with persistence

This class handles:

• Loading saved locale preferences from storage
• Validating that locales are supported by the app
• Persisting locale changes to local storage
• Managing the current locale state

Example usage:

class MyWidget extends ConsumerWidget {
  @override
  Widget build(BuildContext context, WidgetRef ref) {
    final notifier = ref.read(languageSwitcherProvider.notifier);
    final currentLocale = ref.watch(languageSwitcherProvider);

    return ElevatedButton(
      onPressed: () => notifier.changeLocale(const Locale('ar')),
      child: Text('Switch to Arabic'),
    );
  }
}