fix(PostImages, CreatePostScreen): adjust image gap for improved layout consistency

- Reduced image gap in PostImages and CreatePostScreen components from 12 to 4 (desktop) and 8 to 2 (mobile) for better spacing.
- Updated ImageGrid component to modify grid item widths for enhanced layout.
- Refactored PostRepository to improve local caching logic, ensuring non-blocking UI updates during cache writes.
- Introduced saveConversationsWithRelatedCache function to streamline conversation, user, and group data saving in the database.

src/services/database.ts

@@ -991,3 +991,53 @@ export const updateConversationCacheUnreadCount = async (
     }
   });
 };
+
+/**
+ * 批量保存会话列表及其相关数据（用户、群组）
+ * 在单个队列操作中完成，避免多次并发数据库操作导致的 statement 生命周期问题
+ */
+export const saveConversationsWithRelatedCache = async (
+  conversations: ConversationResponse[],
+  users?: UserDTO[],
+  groups?: GroupResponse[]
+): Promise<void> => {
+  if (!conversations || conversations.length === 0) return;
+  
+  const now = new Date().toISOString();
+  
+  await enqueueWrite(async () => {
+    const database = await getDb();
+    
+    // 1. 保存会话列表
+    for (const conversation of conversations) {
+      await database.runAsync(
+        `INSERT OR REPLACE INTO conversation_list_cache (id, data, updatedAt) VALUES (?, ?, ?)`,
+        [
+          String(conversation.id),
+          JSON.stringify(conversation),
+          conversation.updated_at || now,
+        ]
+      );
+    }
+    
+    // 2. 保存用户
+    if (users && users.length > 0) {
+      for (const user of users) {
+        await database.runAsync(
+          `INSERT OR REPLACE INTO users (id, data, updatedAt) VALUES (?, ?, ?)`,
+          [String(user.id), JSON.stringify(user), now]
+        );
+      }
+    }
+    
+    // 3. 保存群组
+    if (groups && groups.length > 0) {
+      for (const group of groups) {
+        await database.runAsync(
+          `INSERT OR REPLACE INTO groups (id, data, updatedAt) VALUES (?, ?, ?)`,
+          [String(group.id), JSON.stringify(group), now]
+        );
+      }
+    }
+  });
+};

src/services/messageService.ts

@@ -25,9 +25,7 @@ import {
   getConversationCache,
   getConversationListCache,
   saveConversationCache,
-  saveConversationsCache,
-  saveGroupsCache,
-  saveUsersCache,
+  saveConversationsWithRelatedCache,
   updateConversationCacheUnreadCount,
 } from './database';
 
@@ -48,18 +46,14 @@ class MessageService {
     list: ConversationResponse[]
   ): Promise<void> {
     if (!list.length) return;
-    await saveConversationsCache(list);
-    await saveUsersCache(
-      list.flatMap(conv => [
-        ...(conv.participants || []),
-        ...(conv.last_message?.sender ? [conv.last_message.sender] : []),
-      ])
-    );
-    await saveGroupsCache(
-      list
-        .map(conv => conv.group)
-        .filter((group): group is NonNullable<typeof group> => Boolean(group))
-    );
+    const users = list.flatMap(conv => [
+      ...(conv.participants || []),
+      ...(conv.last_message?.sender ? [conv.last_message.sender] : []),
+    ]);
+    const groups = list
+      .map(conv => conv.group)
+      .filter((group): group is NonNullable<typeof group> => Boolean(group));
+    await saveConversationsWithRelatedCache(list, users, groups);
   }
 
   /** offset 会话列表单页：请求 + 落库 */