fix(flutter): 重做评论面板视觉

lib/core/theme/app_colors.dart

@@ -55,6 +55,9 @@ abstract final class AppColors {
   static const raised = Color(0xFFFFF1E5);
   static const quick = Color(0xFFFFF0E1);
   static const input = Color(0xFFFFF4EA);
+
+  /// 评论输入框底色。
+  static const commentInput = Color(0xFFF5EFE8);
   static const goldCard = Color(0xFFFFF4DF);
 
   /// 正文颜色。