feat(settings): 添加通知偏好设置和后端 API 集成

apps/lib/features/settings/data/apis/profile_api.dart

@@ -36,6 +36,38 @@ class ProfileApi {
     return _toSettings(data);
   }
 
+  Future<ProfileSettingsV1> updateSettings(ProfileSettingsV1 settings) async {
+    final payload = <String, dynamic>{
+      'settings': {
+        'version': settings.version,
+        'preferences': {
+          'interface_language': settings.preferences.interfaceLanguage,
+          'ai_language': settings.preferences.aiLanguage,
+          'timezone': settings.preferences.timezone,
+          'country': settings.preferences.country,
+        },
+        'privacy': settings.privacy,
+        'notification': {
+          'allow_notifications': settings.notification.allowNotifications,
+          'allow_vibration': settings.notification.allowVibration,
+        },
+      },
+    };
+    final json = await _apiClient.rawDio.patch<Map<String, dynamic>>(
+      '/api/v1/users/me/settings',
+      data: payload,
+    );
+    final data = json.data;
+    if (data is! Map<String, dynamic>) {
+      throw ApiProblem(
+        status: 502,
+        title: 'Invalid settings payload',
+        detail: 'Expected settings response object',
+      );
+    }
+    return _toSettings(data);
+  }
+
   Future<ProfileSettingsV1> uploadAvatar(String filePath) async {
     final formData = FormData.fromMap({
       'file': await MultipartFile.fromFile(filePath),
@@ -71,6 +103,18 @@ class ProfileApi {
           )
         : const PreferenceSettings();
 
+    final notificationRaw = settingsRaw is Map<String, dynamic>
+        ? settingsRaw['notification']
+        : null;
+    final notification = notificationRaw is Map<String, dynamic>
+        ? NotificationSettings(
+            allowNotifications:
+                (notificationRaw['allow_notifications'] as bool? ?? true),
+            allowVibration:
+                (notificationRaw['allow_vibration'] as bool? ?? true),
+          )
+        : const NotificationSettings();
+
     return ProfileSettingsV1(
       displayName: (json['display_name'] as String?) ?? '',
       bio: (json['bio'] as String?) ?? '',
@@ -81,10 +125,7 @@ class ProfileApi {
           ? (settingsRaw['privacy'] as Map<String, dynamic>? ??
                 const <String, dynamic>{})
           : const <String, dynamic>{},
-      notification: settingsRaw is Map<String, dynamic>
-          ? (settingsRaw['notification'] as Map<String, dynamic>? ??
-                const <String, dynamic>{})
-          : const <String, dynamic>{},
+      notification: notification,
     );
   }
 }