feat(push): implement system notification and push framework

frontend/components/layout/sidebar.tsx

@@ -59,6 +59,7 @@ import {
   ShieldCheck,
   Terminal,
   UserRound,
+  Bell,
 } from "lucide-react"
 
 import {useUser} from "@/contexts/user-context"
@@ -75,6 +76,7 @@ const data = {
     { title: "任务管理", url: "/admin/tasks", icon: Layers },
     { title: "存储管理", url: "/admin/files", icon: FolderOpen },
     { title: "数据管理", url: "/admin/database", icon: Database },
+    { title: "通知推送", url: "/admin/push", icon: Bell },
     { title: "系统日志", url: "/admin/logs", icon: Terminal },
     { title: "系统配置", url: "/admin/system", icon: ShieldCheck },
     { title: "系统设置", url: "/admin/settings", icon: Settings },