feat(player): 未就绪改由进度条展示加载态

test/home/home_preview_layout_test.dart

@@ -150,6 +150,8 @@ void main() {
       tester.widget<Text>(find.byKey(const Key('rail-comments-count'))).data,
       '12',
     );
+    expect(find.byKey(const Key('progress-loading')), findsOneWidget);
+    expect(find.byKey(const Key('home-feed-progress-thumb')), findsNothing);
   });
 
   testWidgets('should_seek_and_open_player_from_feed_actions', (tester) async {