Add plugin management to WebUI backend and frontend

Implemented backend API and router for plugin management (list, reload, enable/disable, uninstall) and exposed corresponding frontend controller and dashboard page. Updated navigation and site config to include plugin management. Refactored plugin manager adapter for public methods and improved plugin metadata handling.

packages/napcat-webui-frontend/src/config/site.tsx

@@ -8,6 +8,7 @@ import {
   LuSignal,
   LuTerminal,
   LuZap,
+  LuPackage,
 } from 'react-icons/lu';
 
 export type SiteConfig = typeof siteConfig;
@@ -59,6 +60,11 @@ export const siteConfig = {
       icon: <LuFolderOpen className='w-5 h-5' />,
       href: '/file_manager',
     },
+    {
+      label: '插件管理',
+      icon: <LuPackage className='w-5 h-5' />,
+      href: '/plugins',
+    },
     {
       label: '系统终端',
       icon: <LuTerminal className='w-5 h-5' />,