feat: 添加举报功能前端支持

- 新增 reportService API 服务
- 新增 ReportDialog 举报对话框组件
- 集成举报入口到 PostCard、CommentItem、LongPressMenu

Made-with: Cursor

src/screens/message/components/ChatScreen/types.ts

@@ -166,6 +166,7 @@ export interface LongPressMenuProps {
   onRecall: (messageId: string) => void;
   onDelete: (messageId: string) => void;
   onAddSticker?: (imageUrl: string) => void;
+  onReport?: (message: GroupMessage) => void; // 举报消息回调
 }
 
 // 聊天头部 Props