feat: 长辈模式（大字大按钮 + 偏好按账号隔离）+ 语音输入（按住说话 + 实时转写 + 后端代理 DashScope ASR + 患者端专用）+ 健康仪表盘背景渐变

health_app/lib/core/app_router.dart

@@ -11,6 +11,7 @@ import '../pages/report/report_pages.dart';
 import '../pages/report/ai_analysis_page.dart';
 import '../pages/consultation/consultation_pages.dart';
 import '../pages/settings/settings_pages.dart';
+import '../pages/settings/elder_mode_page.dart';
 import '../pages/settings/notification_prefs_page.dart';
 import '../pages/notifications/notification_center_page.dart';
 import '../pages/history/conversation_history_page.dart';
@@ -127,6 +128,8 @@ Widget buildPage(RouteInfo route, WidgetRef ref) {
       return const FollowUpListPage();
     case 'settings':
       return const SettingsPage();
+    case 'elderMode':
+      return const ElderModePage();
     case 'notificationPrefs':
       return const NotificationPrefsPage();
     case 'notifications':