feat(messaging): implement optimistic updates with retry for failed messages

- Add pending/failed message status to track send state
- Implement optimistic UI: show message immediately, update on server response
- Add retry functionality for failed messages via tap-to-retry
- Change send button from icon to text "发送" for clarity
- Add MessageSendService with temp ID generation to prevent collisions

feat(notification): add JPush notification deduplication and clear on tap

- Deduplicate notificationArrived events from dual JPush/vendor channels
- Clear all notifications on tap (QQ-style behavior)

feat(post): add client-side idempotency key for post creation

- Generate client_request_id per publish intent to prevent duplicates on retry
- Pass idempotency key through to postService and voteService

src/services/post/voteService.ts

@@ -58,6 +58,7 @@ class VoteService {
       segments,
       images: data.images,
       channel_id: data.channel_id,
+      client_request_id: data.client_request_id,
     });
     return response.data;
   }