feat(app): 完善播放协议搜索与空状态

test/core/subpage_header_test.dart

@@ -97,8 +97,8 @@ void main() {
     );
     expect(material.color, AppColors.headerScrim);
     expect(icon.color, AppColors.onSurface);
-    expect(icon.size, 22);
-    expect(icon.weight, 600);
+    expect(icon.size, 34);
+    expect(icon.weight, 400);
     final shadow =
         tester
                 .widget<DecoratedBox>(