feat(flutter): 统一文字下拉刷新

lib/pages/discover/discover_view.dart

@@ -14,6 +14,7 @@ import '../../core/theme/app_colors.dart';
 import '../../core/theme/app_dimens.dart';
 import '../../core/theme/app_theme.dart';
 import '../../core/widgets/app_bottom_nav.dart';
+import '../../core/widgets/app_pull_to_refresh.dart';
 import '../../core/widgets/empty_state.dart';
 import '../../l10n/app_localizations.dart';
 import '../filter/filter_page.dart';
@@ -152,11 +153,8 @@ class _DiscoverPageState extends State<DiscoverPage> {
       child: Stack(
         children: [
           Positioned.fill(
-            child: RefreshIndicator(
+            child: AppPullToRefresh(
               key: const Key('discover-refresh'),
-              color: AppColors.blue,
-              backgroundColor: AppColors.card,
-              strokeWidth: 2,
               edgeOffset: _stickyHeaderHeight + 8,
               onRefresh: categories.load,
               child: ListView(