多端同步与消息漫游

// 多端一致性的最小实现：消息去重 + 前台刷新 + KICKED 处理
const seen = new Set(); // 生产建议持久化（按会话 + messageId）

client.addEventListener(Events.MESSAGES, ({ messages }) => {
  const fresh = messages.filter((m) => !seen.has(m.messageId));
  fresh.forEach((m) => seen.add(m.messageId));
  if (fresh.length) render(fresh); // 只渲染新消息，避免重复
});

document.addEventListener('visibilitychange', async () => {
  if (document.visibilityState !== 'visible') return;
  // 回到前台：重新拉会话列表与当前会话历史，校正未读/撤回/多端操作
  const conversations = await client.getConversationList();
  renderConversations(conversations.data);
  if (current) {
    const page = await client.getHistoryMessages(current.type, current.targetId, { limit: 20 });
    renderHistory(page.data);
    await client.clearUnreadCount(current.type, current.targetId);
  }
});

client.addEventListener(Events.KICKED, ({ code, reason }) => {
  clearInterval(pollTimer);
  disconnectAndLogout({ code, reason });
});