feat: add login authentication and certificate expiry notifications

- JWT-based login with ADMIN_USER/ADMIN_PASSWORD env config
- Login page with auth guard for Vue frontend
- Feishu bot webhook notification for expiring certificates
- SMTP email notification for expiring certificates
- Daily 8:00 AM cron for expiry checks
- Startup health check notification

frontend/src/router/index.ts

@@ -2,14 +2,57 @@ import { createRouter, createWebHistory } from 'vue-router'
 import Dashboard from '../views/Dashboard.vue'
 import CertList from '../views/CertList.vue'
 import CertCreate from '../views/CertCreate.vue'
+import Login from '../views/Login.vue'
+import { isLoggedIn } from '../api'
 
 const router = createRouter({
   history: createWebHistory(),
   routes: [
-    { path: '/', name: 'Dashboard', component: Dashboard },
-    { path: '/certificates', name: 'CertList', component: CertList },
-    { path: '/create', name: 'CertCreate', component: CertCreate },
+    {
+      path: '/login',
+      name: 'Login',
+      component: Login,
+      meta: { requiresAuth: false },
+    },
+    {
+      path: '/',
+      name: 'Dashboard',
+      component: Dashboard,
+      meta: { requiresAuth: true },
+    },
+    {
+      path: '/certificates',
+      name: 'CertList',
+      component: CertList,
+      meta: { requiresAuth: true },
+    },
+    {
+      path: '/create',
+      name: 'CertCreate',
+      component: CertCreate,
+      meta: { requiresAuth: true },
+    },
   ],
 })
 
+// Navigation guard
+router.beforeEach((to, _, next) => {
+  const requiresAuth = to.meta.requiresAuth !== false
+
+  if (requiresAuth) {
+    if (isLoggedIn()) {
+      next()
+    } else {
+      next({ name: 'Login', query: { redirect: to.fullPath } })
+    }
+  } else {
+    // If already logged in and going to login, redirect to dashboard
+    if (to.name === 'Login' && isLoggedIn()) {
+      next({ name: 'Dashboard' })
+    } else {
+      next()
+    }
+  }
+})
+
 export default router