第七轮深度测试：修复7个agent发现的12处前端问题，重点是列表分页截断与呼叫/播放状态机

- 通话状态机（Ch8）：canStartCall 补齐通话中重复发起的防护，callShouldStart 补齐放弃/失败路径的清理
- 分页截断（Ch5-6）：新增 fetchAllPages 辅助函数，修复通讯录/黑名单/好友申请/群成员/管理员/禁言等
  11 处列表只读首页导致真实成员被遗漏的问题；群角色判断改用不受分页影响的 getGroup().my_role
- 消息与媒体（Ch3-4/Ch7/Ch9）：录音超时污染时长、手动重试丢失 head 导致消息被错误分类、批量删除
  未取消上传中附件、语音播放器补齐同时只能播一条、workplace-collaboration-view 冗余重试请求
- 独立密码/青少年模式（Ch10-11）：设置密码后按调用来源判断是否应自动开启青少年模式，避免关闭流程
  中途"忘记密码"被误当成开启；注销账号确认文案补充群主后果说明

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

src/views/messages-view.jsx

@@ -1346,7 +1346,17 @@ class MessagesView extends React.Component {
     if (!topic || !this.props.selectedSeqs.length) {
       return;
     }
-    topic.delMessagesList(this.props.selectedSeqs.slice(), true).then(_ => {
+    // A selected message may still be queued/uploading (no server-confirmed seq yet, same case
+    // context-menu.jsx's single-message deleteMessages guards with cancelSend before falling
+    // back to delMessagesList). delMessagesList's normalizeRanges silently drops local-only
+    // seqs instead of cancelling them, so left unfiltered a still-uploading attachment would
+    // survive "delete" and get sent normally once its upload finishes.
+    const remaining = this.props.selectedSeqs.filter(seq => !topic.cancelSend(seq));
+    if (!remaining.length) {
+      this.props.onExitSelectMode();
+      return;
+    }
+    topic.delMessagesList(remaining, true).then(_ => {
       this.props.onExitSelectMode();
     }).catch(err => {
       this.props.onError(err.message, 'err');