refactor(ProcessPostUseCase, useCursorPagination, useDifferentialPosts): enhance post merging and loading states

- Introduced new methods for merging posts and comments efficiently, improving performance during data updates.
- Updated loading state management in hooks to include initial loading and loading more states for better user feedback.
- Refactored HomeScreen and PostDetailScreen to utilize the new loading states and merging logic, enhancing user experience during data fetching.
- Improved pagination handling in useCursorPagination and useDifferentialPosts to ensure consistent data management across components.

src/screens/home/HomeScreen.tsx

@@ -119,6 +119,8 @@ export const HomeScreen: React.FC = () => {
   const {
     posts,
     loading: isLoading,
+    isInitialLoading,
+    isLoadingMore,
     refreshing: isRefreshing,
     hasMore,
     error,
@@ -135,17 +137,23 @@ export const HomeScreen: React.FC = () => {
 
   // 加载更多方法
   const loadMore = useCallback(async () => {
-    if (hasMore && !isLoading && !isLoadingMoreRef.current) {
+    if (hasMore && !isLoadingMore && !isLoadingMoreRef.current) {
       isLoadingMoreRef.current = true;
+      const startedAt = Date.now();
       try {
         await processPostUseCase.loadMorePosts(listKey);
+        console.log('[PostPerf] home loadMore', {
+          listKey,
+          costMs: Date.now() - startedAt,
+          totalItems: posts.length,
+        });
       } catch (err) {
         console.error('加载更多失败:', err);
       } finally {
         isLoadingMoreRef.current = false;
       }
     }
-  }, [listKey, hasMore, isLoading]);
+  }, [posts.length, listKey, hasMore, isLoadingMore]);
   
   // 网格模式滚动处理 - 检测是否滚动到底部
   const handleGridScroll = useCallback((event: any) => {
@@ -366,7 +374,9 @@ export const HomeScreen: React.FC = () => {
   };
 
   // 渲染帖子卡片（列表模式）
-  const renderPostList = ({ item }: { item: Post }) => {
+  const keyExtractor = useCallback((item: Post) => item.id, []);
+
+  const renderPostList = useCallback(({ item }: { item: Post }) => {
     const authorId = item.author?.id || '';
     const isPostAuthor = currentUser?.id === authorId;
     return (
@@ -394,7 +404,7 @@ export const HomeScreen: React.FC = () => {
         />
       </View>
     );
-  };
+  }, [currentUser?.id, handleBookmark, handleDeletePost, handleImagePress, handleLike, handlePostPress, handleShare, handleUserPress, isMobile, listItemWidth, responsiveGap]);
 
   // 估算帖子在瀑布流中的高度（用于均匀分配）
   const estimatePostHeight = (post: Post, columnWidth: number): number => {
@@ -558,8 +568,8 @@ export const HomeScreen: React.FC = () => {
   };
 
   // 渲染空状态
-  const renderEmpty = () => {
-    if (isLoading) return null;
+  const renderEmpty = useCallback(() => {
+    if (isInitialLoading) return null;
     
     return (
       <EmptyState
@@ -567,7 +577,7 @@ export const HomeScreen: React.FC = () => {
         description={activeIndex === 1 ? '关注一些用户来获取内容吧' : '暂无帖子，快去发布第一条内容吧'}
       />
     );
-  };
+  }, [activeIndex, isInitialLoading]);
 
   // 渲染列表内容
   const renderListContent = () => {
@@ -581,7 +591,7 @@ export const HomeScreen: React.FC = () => {
       <FlatList
         data={displayPosts}
         renderItem={renderPostList}
-        keyExtractor={item => item.id}
+        keyExtractor={keyExtractor}
         contentContainerStyle={[
           styles.listContent,
           {
@@ -602,7 +612,12 @@ export const HomeScreen: React.FC = () => {
         onEndReached={loadMore}
         onEndReachedThreshold={0.3}
         ListEmptyComponent={renderEmpty}
-        ListFooterComponent={isLoading ? <Loading size="sm" /> : null}
+        ListFooterComponent={isLoadingMore ? <Loading size="sm" /> : null}
+        initialNumToRender={8}
+        maxToRenderPerBatch={8}
+        updateCellsBatchingPeriod={60}
+        windowSize={7}
+        removeClippedSubviews
       />
     );
   };
@@ -661,7 +676,9 @@ export const HomeScreen: React.FC = () => {
         // 移动端：使用 GestureDetector 支持手势切换 Tab
         <GestureDetector gesture={swipeGesture}>
           <View style={styles.contentContainer}>
-            {viewMode === 'list' ? (
+            {isInitialLoading ? (
+              <Loading fullScreen />
+            ) : viewMode === 'list' ? (
               renderListContent()
             ) : (
               // 网格模式：使用响应式网格
@@ -672,7 +689,9 @@ export const HomeScreen: React.FC = () => {
       ) : (
         // 桌面端/平板端：不使用 GestureDetector，避免拦截侧边栏点击
         <View style={styles.contentContainer}>
-          {viewMode === 'list' ? (
+          {isInitialLoading ? (
+            <Loading fullScreen />
+          ) : viewMode === 'list' ? (
             renderListContent()
           ) : (
             // 网格模式：使用响应式网格