feat(media): 图片占位改为纯色块并去掉扫光

lib/pages/recommend/widgets/home_hero_carousel.dart

@@ -187,7 +187,6 @@ class _HomeHeroCarouselState extends State<HomeHeroCarousel> {
         RemoteImage(
           banner.imageUrl,
           fit: BoxFit.cover,
-          showFallbackIcon: true,
           fallbackColor: AppColors.contentSurface,
         ),
         const DecoratedBox(
@@ -210,10 +209,7 @@ class _HomeHeroCarouselState extends State<HomeHeroCarousel> {
             left: 28,
             right: 28,
             bottom: _copyBottomInset,
-            child: _HeroCopy(
-              key: Key('home-hero-copy-$index'),
-              drama: drama,
-            ),
+            child: _HeroCopy(key: Key('home-hero-copy-$index'), drama: drama),
           ),
         if (drama != null)
           Positioned.fill(