fix: 恢复用户菜单（修改昵称/修改密码）

- userInfo 添加 onclick 触发用户菜单
- 添加 userMenu 下拉菜单（修改昵称/修改密码）
- 点击页面其他位置关闭菜单

frontend/analysis.html

@@ -90,7 +90,13 @@ body{font-family:-apple-system,BlinkMacSystemFont,"SF Pro Display","PingFang SC"
           <div class="notif-list" id="notifList"><div class="notif-empty">暂无通知</div></div>
         </div>
       </div>
-      <span class="user-info" id="userInfo"></span>
+      <div class="export-wrap">
+        <span class="user-info" id="userInfo" onclick="toggleUserMenu(event)"></span>
+        <div class="export-menu" id="userMenu">
+          <a href="#" onclick="showChangeNick(event)">修改昵称</a>
+          <a href="#" onclick="showChangePwd(event)">修改密码</a>
+        </div>
+      </div>
       <a href="/admin.html" class="admin-link" id="adminLink" style="display:none">管理</a>
       <div class="export-wrap">
         <button class="hdr-btn" onclick="toggleExport(event)">导出</button>
@@ -144,6 +150,7 @@ async function apiFetch(path,opts={}){
   return res;
 }
 
+function toggleUserMenu(e){e.stopPropagation();$('userMenu').classList.toggle('show');}
 async function checkAuth(){
   if(!token){window.location.href='/';return false;}
   const res=await apiFetch('/auth/profile');