feat(message): implement version-based incremental sync and WS compression

Implement a more efficient conversation synchronization mechanism using
version numbers instead of sequence numbers to reduce bandwidth usage.
This includes adding support for Gzip decompression on WebSocket
messages to optimize data transfer.

- Add `pako` for WebSocket message decompression
- Implement `getSyncByVersion` in `MessageService`
- Implement `syncByVersion` in `MessageSyncService` to handle incremental
  updates and conversation state changes
- Update `WebSocketService` to support binary frames and Gzip inflation
- Add `syncVersion` to `MessageStore` for tracking synchronization state

src/services/message/messageService.ts

@@ -476,6 +476,37 @@ class MessageService {
     return response.data?.conversations || [];
   }
 
+  /**
+   * 增量同步（基于版本号）
+   * GET /api/v1/conversations/sync?version=N&limit=100
+   */
+  async getSyncByVersion(version: number, limit: number = 100): Promise<{
+    current_version: number;
+    changes: Array<{
+      conversation_id: string;
+      change_type: string;
+      max_seq?: number;
+      last_message_at?: number;
+      version: number;
+    }>;
+    full_sync: boolean;
+    has_more: boolean;
+  }> {
+    const response = await api.get<{
+      current_version: number;
+      changes: Array<{
+        conversation_id: string;
+        change_type: string;
+        max_seq?: number;
+        last_message_at?: number;
+        version: number;
+      }>;
+      full_sync: boolean;
+      has_more: boolean;
+    }>('/conversations/sync', { version, limit });
+    return response.data;
+  }
+
   /**
    * 获取系统消息未读数
    * GET /api/v1/messages/system/unread-count