fix(ui): 收敛骨架屏亮度

lib/core/theme/app_colors.dart

@@ -78,7 +78,7 @@ abstract final class AppColors {
   /// 中性深灰卡片与控件表面。
   static const contentCard = Color(0xFF16161A);
   static const contentSurface = Color(0xFF1C1C1E);
-  static const skeletonSurface = Color(0xFF141414);
+  static const skeletonSurface = Color(0xFF0E0E0E);
   static const contentChip = Color(0xFF2C2C2E);
   static const contentBorder = Color(0x1AFFFFFF);
   static const filterChipSelected = Color(0xFF21090E);

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 {