🐛 Fix explore pagination placeholder maxWidth

lib/screens/explore.dart

@@ -317,7 +317,7 @@ class ExploreScreen extends HookConsumerWidget {
       // Sliver list cannot provide refresh handled by the pagination list
       isRefreshable: false,
       isSliver: true,
-      footerSkeletonChild: const PostItemSkeleton(),
+      footerSkeletonChild: const PostItemSkeleton(maxWidth: double.infinity),
       contentBuilder: (data, footer) =>
           _ActivityListView(data: data, isWide: isWide, footer: footer),
     );

lib/widgets/post/post_item_skeleton.dart

@@ -10,6 +10,7 @@ class PostItemSkeleton extends StatelessWidget {
   final bool isEmbedReply;
   final bool isCompact;
   final double? borderRadius;
+  final double maxWidth;
 
   const PostItemSkeleton({
     super.key,
@@ -19,6 +20,7 @@ class PostItemSkeleton extends StatelessWidget {
     this.isEmbedReply = false,
     this.isCompact = false,
     this.borderRadius,
+    this.maxWidth = 640,
   });
 
   @override
@@ -28,7 +30,7 @@ class PostItemSkeleton extends StatelessWidget {
 
     return Center(
       child: ConstrainedBox(
-        constraints: BoxConstraints(maxWidth: 640),
+        constraints: BoxConstraints(maxWidth: maxWidth),
         child: Card(
           margin: EdgeInsets.only(bottom: 8),
           child: Column(