fix: 移除所有权限身份显示，QR上传布局还原为initial commit样式

frontend/src/components/UserMenu.vue

@@ -2,9 +2,6 @@
   <div class="usermenu-overlay" @click.self="$emit('close')">
     <div class="usermenu-card">
       <div class="usermenu-name">{{ auth.user.display_name || auth.user.username }}</div>
-      <div class="usermenu-role">
-        <span class="role-badge">{{ roleLabel }}</span>
-      </div>
 
       <div class="usermenu-actions">
         <button class="usermenu-btn" @click="goMyDiary">
@@ -71,16 +68,6 @@ const bugContent = ref('')
 
 const unreadCount = computed(() => notifications.value.filter(n => !n.is_read).length)
 
-const roleLabel = computed(() => {
-  const map = {
-    admin: '管理员',
-    senior_editor: '高级编辑',
-    editor: '编辑',
-    viewer: '查看者',
-  }
-  return map[auth.user.role] || auth.user.role
-})
-
 function formatTime(d) {
   if (!d) return ''
   return new Date(d + 'Z').toLocaleString('zh-CN', { month: 'short', day: 'numeric', hour: '2-digit', minute: '2-digit' })
@@ -162,13 +149,7 @@ onMounted(loadNotifications)
   z-index: 4001;
 }
 
-.usermenu-name { font-size: 16px; font-weight: 600; color: #3e3a44; margin-bottom: 4px; }
-.usermenu-role { margin-bottom: 14px; }
-.role-badge {
-  display: inline-block; font-size: 11px; padding: 2px 10px;
-  border-radius: 8px; background: linear-gradient(135deg, #e8f5e9, #c8e6c9);
-  color: #4a9d7e; font-weight: 500;
-}
+.usermenu-name { font-size: 16px; font-weight: 600; color: #3e3a44; margin-bottom: 14px; }
 
 .usermenu-actions { display: flex; flex-direction: column; gap: 4px; }
 .usermenu-btn {