feat(notification): 通知标题和正文支持多语言

- 通知静态配置支持 title/body i18n
- 前端通知列表和详情页展示本地化内容
- 新增数据库迁移脚本
- 更新通知协议文档

apps/lib/features/notifications/presentation/bloc/notification_bloc.dart

@@ -15,6 +15,7 @@ class NotificationState {
     this.unreadCount = 0,
     this.hasMore = false,
     this.nextCursor,
+    this.isLoadingMore = false,
     this.errorMessage,
   });
 
@@ -23,6 +24,7 @@ class NotificationState {
   final int unreadCount;
   final bool hasMore;
   final String? nextCursor;
+  final bool isLoadingMore;
   final String? errorMessage;
 
   NotificationState copyWith({
@@ -31,6 +33,7 @@ class NotificationState {
     int? unreadCount,
     bool? hasMore,
     String? nextCursor,
+    bool? isLoadingMore,
     String? errorMessage,
   }) {
     return NotificationState(
@@ -39,6 +42,7 @@ class NotificationState {
       unreadCount: unreadCount ?? this.unreadCount,
       hasMore: hasMore ?? this.hasMore,
       nextCursor: nextCursor ?? this.nextCursor,
+      isLoadingMore: isLoadingMore ?? this.isLoadingMore,
       errorMessage: errorMessage ?? this.errorMessage,
     );
   }
@@ -81,10 +85,13 @@ final class NotificationRevokedEvent extends NotificationEvent {
 }
 
 class NotificationBloc extends ChangeNotifier {
-  NotificationBloc({required NotificationRepository repository})
-    : _repository = repository;
+  NotificationBloc({
+    required NotificationRepository repository,
+    this.locale = 'zh',
+  }) : _repository = repository;
 
   final NotificationRepository _repository;
+  final String locale;
   final Logger _logger = getLogger('features.notifications.bloc');
   NotificationState _state = const NotificationState();
 
@@ -119,7 +126,10 @@ class NotificationBloc extends ChangeNotifier {
     notifyListeners();
 
     try {
-      final result = await _repository.listNotifications(limit: 20);
+      final result = await _repository.listNotifications(
+        limit: 20,
+        locale: locale,
+      );
       _state = _state.copyWith(
         status: NotificationStatus.loaded,
         items: result.items,
@@ -143,7 +153,10 @@ class NotificationBloc extends ChangeNotifier {
 
   Future<void> _refreshNotifications() async {
     try {
-      final result = await _repository.listNotifications(limit: 20);
+      final result = await _repository.listNotifications(
+        limit: 20,
+        locale: locale,
+      );
       _state = _state.copyWith(
         status: NotificationStatus.loaded,
         items: result.items,
@@ -161,18 +174,25 @@ class NotificationBloc extends ChangeNotifier {
   }
 
   Future<void> _loadMore() async {
-    if (!_state.hasMore || _state.nextCursor == null) return;
+    if (_state.isLoadingMore || !_state.hasMore || _state.nextCursor == null) {
+      return;
+    }
+
+    _state = _state.copyWith(isLoadingMore: true);
+    notifyListeners();
 
     try {
       final result = await _repository.listNotifications(
         limit: 20,
         cursor: _state.nextCursor,
+        locale: locale,
       );
       final allItems = [..._state.items, ...result.items];
       _state = _state.copyWith(
         items: allItems,
         hasMore: result.hasMore,
         nextCursor: result.nextCursor,
+        isLoadingMore: false,
       );
       notifyListeners();
     } catch (error, stackTrace) {
@@ -181,6 +201,8 @@ class NotificationBloc extends ChangeNotifier {
         error: error,
         stackTrace: stackTrace,
       );
+      _state = _state.copyWith(isLoadingMore: false);
+      notifyListeners();
     }
   }
 
@@ -197,6 +219,7 @@ class NotificationBloc extends ChangeNotifier {
     try {
       final updated = await _repository.markRead(
         notificationId: notificationId,
+        locale: locale,
       );
       final targetIndex = _state.items.indexWhere(
         (item) => item.id == updated.id,