feat: add auth routing and role guards

frontend/src/router.ts

@@ -0,0 +1,15 @@
+import { createRouter, createWebHistory } from 'vue-router'
+import App from './App.vue'
+import { getCurrentUser } from './services/auth'
+import type { UserRole } from './types/auth'
+
+let role:UserRole|undefined
+const router=createRouter({history:createWebHistory(),routes:[
+  {path:'/',component:App},
+  {path:'/login',component:()=>import('./views/LoginView.vue'),meta:{public:true}},
+  {path:'/register',component:()=>import('./views/RegisterView.vue'),meta:{public:true}},
+  {path:'/profile',component:()=>import('./views/ProfileView.vue')},
+  {path:'/admin',component:()=>import('./views/AdminView.vue'),meta:{role:'admin'}},
+]})
+router.beforeEach(async to=>{if(to.meta.public)return true;try{role=(await getCurrentUser()).role}catch{return {path:'/login',query:{redirect:to.fullPath}}}if(to.meta.role&&role!==to.meta.role)return {path:'/profile',query:{forbidden:'1'}};return true})
+export default router