✨ 添加管理员标签页持久化功能

- 刷新页面后管理员标签页保持不变（概览/设置/监控/用户/工具）
- 使用localStorage存储当前标签页状态
- 登出时自动清理保存的标签页状态

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

frontend/app.js

@@ -1003,6 +1003,7 @@ handleDragLeave(e) {
       this.stopTokenRefresh();
       localStorage.removeItem('user');
       localStorage.removeItem('lastView');
+      localStorage.removeItem('adminTab');
       this.showResendVerify = false;
       this.resendVerifyEmail = '';
 
@@ -1066,6 +1067,14 @@ handleDragLeave(e) {
             targetView = 'files';
           }
 
+          // 恢复管理员标签页
+          if (this.user.is_admin) {
+            const savedAdminTab = localStorage.getItem('adminTab');
+            if (savedAdminTab && ['overview', 'settings', 'monitor', 'users', 'tools'].includes(savedAdminTab)) {
+              this.adminTab = savedAdminTab;
+            }
+          }
+
           // 强制切换到目标视图并加载数据
           this.switchView(targetView, true);
         }
@@ -2886,6 +2895,12 @@ handleDragLeave(e) {
       if (this.isLoggedIn && this.isViewAllowed(newView)) {
         localStorage.setItem('lastView', newView);
       }
+    },
+    // 记住管理员当前标签页
+    adminTab(newTab) {
+      if (this.isLoggedIn && this.user?.is_admin) {
+        localStorage.setItem('adminTab', newTab);
+      }
     }
   }
 }).mount('#app');