refactor: simplify auth and subscription links

frontend/src/layouts/AdminLayout.vue

@@ -47,7 +47,6 @@ const menu = [
   { to: '/sources', icon: '📡', label: '订阅源' },
   { to: '/collections', icon: '📁', label: '合集' },
   { to: '/templates', icon: '📋', label: '模板' },
-  { to: '/shares', icon: '🔗', label: '分享' },
   { to: '/recycle-bin', icon: '♻️', label: '回收站' },
   { to: '/tools', icon: '🔧', label: '工具' },
   { to: '/settings', icon: '⚙️', label: '设置' },