feat(flutter): 首页网格改为三列并首位显示全部

lib/pages/discover/discover_view.dart

@@ -270,7 +270,7 @@ class _DiscoverPageState extends State<DiscoverPage> {
 
   Widget _categories(AppLocalizations l10n, CategoryController categories) {
     final choices = <({String code, String label})>[
-      (code: CategoryController.allCode, label: l10n.forYou),
+      (code: CategoryController.allCode, label: l10n.all),
       (code: CategoryController.hotCode, label: l10n.hot),
       (code: CategoryController.newCode, label: l10n.newest),
       for (final category in categories.categories)