整理router，删除多余中单件和路由。退出按键放最上方。

templates/admin/index.html

@@ -8,12 +8,15 @@
     <link rel="stylesheet" href="/static/css/adminstyle.css?v=3">
 </head>
 <body>
+    <div class="admin-header">
+        <h2>GoBlog</h2>
+        <span id="username">{{.DisplayName}}</span>
+        <span id="logout-btn">退出</span>
+    </div>
+
     <div id="app">
         <aside class="sidebar">
-            <div class="logo">
-                <h2>GoBlog</h2>
-                <p>后台管理</p>
-            </div>
+
             <nav class="menu">
                 {{range .Menus}}{{if eq .Group ""}}{{range $i, $item := .Items}}<a href="#{{$item.Key}}" class="menu-item{{if eq $item.Key "dashboard"}} active{{end}}" data-page="{{$item.Key}}">{{$item.Name}}</a>
                 {{end}}{{else}}
@@ -26,10 +29,6 @@
                 </div>
                 {{end}}{{end}}
             </nav>
-            <div class="user-info">
-                <span id="username">{{.DisplayName}}</span>
-                <button id="logout-btn">退出</button>
-            </div>
         </aside>
 
         <main class="main-content">