Clarify auth states

middleware/auth.global.ts

@@ -2,6 +2,8 @@ export default defineNuxtRouteMiddleware(async (to) => {
   if (to.path === '/login' || to.path.startsWith('/share/')) return
 
   const session = useState<{ id: string; email: string; name: string } | null>('session')
+  const sessionCookie = useCookie<string | null>('money_session')
+  const authReason = sessionCookie.value ? 'expired' : 'required'
 
   if (session.value === undefined) {
     try {
@@ -12,6 +14,12 @@ export default defineNuxtRouteMiddleware(async (to) => {
   }
 
   if (!session.value) {
-    return navigateTo('/login')
+    return navigateTo({
+      path: '/login',
+      query: {
+        reason: authReason,
+        redirect: to.fullPath === '/' ? undefined : to.fullPath
+      }
+    })
   }
 })