fix(ui): 收敛骨架屏亮度

lib/core/widgets/drama_grid_skeleton.dart

@@ -11,7 +11,7 @@ const Duration _shimmerPeriod = Duration(milliseconds: 1400);
 const double _shimmerTravel = 2.4;
 const double _shimmerStart = -1.2;
 const double _subtitleWidthFactor = 0.62;
-const Color _shimmerHighlight = Color(0x38FFFFFF);
+const Color _shimmerHighlight = Color(0x12FFFFFF);
 
 /// 首页短剧网格的占位。行数至少铺满可视高度，并带一道扫光。
 class DramaGridSkeleton extends StatefulWidget {