修复禅道Bug清单中的前端问题：好友申请source校验、群解散二次验证缺失、

群解散事件未处理、错误码翻译缺失、恢复登录页误导性提示

- 好友申请首次必失败30000（P0）：AddFriendModal把手机号搜索单独标记为
  source:"phone"上报，但后端serveIMFriendRequestCreate的source校验只认
  search/qr/group，命中default分支返回"invalid friend request source"。
  改为手机号搜索也统一上报source:"search"（后端本就不区分具体搜索渠道），
  用两个全新、此前无任何关系的测试账号验证首次申请200成功
- 解散群聊需要短信二次验证但完整流程从未实现（P0）：新增
  SecurityChallengeModal通用二次验证弹层（POST /security/challenges→
  验证码→verify→action_token）+ requestActionToken()（stores/
  securityChallenge.ts，与requestConfirm同一模式），接入解散群聊和转让
  群主（后者此前也因缺X-Action-Token必然404/400）。同时发现并修复
  imDelete对无body请求不显式传空对象体，导致携带Content-Type:
  application/json但请求体真正为空时后端JSON解码失败返回400——实测确认
  两个问题都解决后DELETE返回200
- 群聊被解散但当前正查看该群的用户界面不会跳转（P1）：新增
  topics.ts的subscribeTopicGone()监听SDK自身的onDeleteTopic回调，
  ConversationView据此在当前会话被解散时弹出提示并跳转回消息列表
- P2P会话发起方标题栏显示原始topic id、对方明明在线却显示离线：确认
  为上一轮已修复的isCommType()根因问题的同一症状，本轮实测（新建从未
  聊过天的账号对）已不再复现；群内消息发送者显示原始uid的关联描述同样
  实测未复现
- 好友关系冲突（已是好友/申请正在处理中）报错英文原文透出：翻译表补充
  FRIEND_REQUEST_CONFLICT
- 深链/刷新页面时的"改为重新登录"链接此前在任何恢复登录过程中都会
  立即显示（不管是否超时），造成短暂白屏时的误导性提示：改为仅在真正
  超时后才显示该链接，与其上方的提示文案保持一致的显示条件

web/src/features/messages/ConversationView.tsx

@@ -29,10 +29,10 @@ import { buildMentionedContent, detectMentionTrigger, type PendingMention } from
 import { sendFile, sendImage, sendVoice } from '@/lib/tinode/attachments';
 import { useChatList, useTinode, useTopicMessages } from '@/lib/tinode/hooks';
 import { forwardMessage, sendPrebuiltContent, sendReply, sendText } from '@/lib/tinode/send';
-import { closeConversation, ensureTopicAttached, openConversation } from '@/lib/tinode/topics';
+import { closeConversation, ensureTopicAttached, openConversation, subscribeTopicGone } from '@/lib/tinode/topics';
 import { useCallStore } from '@/stores/calls';
 import { requestConfirm } from '@/stores/confirmDialog';
-import { notImplemented } from '@/stores/globalToast';
+import { notify, notImplemented } from '@/stores/globalToast';
 import { useMessageJumpStore } from '@/stores/messageJump';
 import { useSessionStore } from '@/stores/session';
 
@@ -165,6 +165,20 @@ export function ConversationView() {
     // eslint-disable-next-line react-hooks/exhaustive-deps
   }, [topicId]);
 
+  // Someone else dissolving the group currently open here (or this account being removed from it)
+  // fires the SDK's `onDeleteTopic`, not `onData`/`onPres` -- those only invalidate this screen's
+  // cached snapshots for re-render, they don't tell it the topic itself is gone. Left unhandled, the
+  // member who happened to be looking at that conversation just keeps staring at a now-defunct screen
+  // (an actual reported bug: staying on the dissolved group's view with no way back except a manual
+  // nav). `notify()` (the global toast, not this screen's own `errorToast`) survives the navigate.
+  useEffect(() => {
+    return subscribeTopicGone((goneTopicName) => {
+      if (goneTopicName !== topicId) return;
+      notify('该群聊已解散');
+      navigate('/messages', { replace: true });
+    });
+  }, [topicId, navigate]);
+
   // useLayoutEffect, not useEffect -- this component never remounts on topicId change (route is
   // `:topicId`), so a plain useEffect (which fires after paint) can let one frame render with the
   // PREVIOUS conversation's select-mode/menu/etc. still showing over the new conversation's message