feat: 开屏后直接展示首页骨架

lib/core/theme/app_colors.dart

@@ -78,6 +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 contentChip = Color(0xFF2C2C2E);
   static const contentBorder = Color(0x1AFFFFFF);
   static const filterChipSelected = Color(0xFF21090E);

lib/core/theme/app_dimens.dart

@@ -110,6 +110,11 @@ abstract final class AppDimens {
   static const double cardBadgeFont = 9;
   static const double cardCoverTitleGap = 6;
   static const double cardTitleTagGap = 6;
+  static const double skeletonBarHeight = 10;
+  static const double skeletonBarRadius = 4;
+  static const double skeletonBarGap = 4;
+  static const double skeletonTitleBarGap = 3;
+  static const double skeletonBodyExtent = 34;
   static const double cardCoverAspectRatio = 3 / 4;
   static const double homeCardBodyExtent = 84;
   static const double homePrimaryTabFont = 18;