fix(portal): access ref value in login form submission

form is a ref() — in <script setup>, .value is required to access
the inner object. form.email was undefined at runtime, causing a
TypeError that was caught and shown as the generic login error.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

apps/portal/src/pages/login.vue

@@ -55,7 +55,7 @@ async function onSubmit(): Promise<void> {
   errorMessage.value = ''
   isSubmitting.value = true
   try {
-    await authStore.login(form.email.trim(), form.password)
+    await authStore.login(form.value.email.trim(), form.value.password)
     await portalStore.hydrateAfterAuth()
     const redirect = typeof route.query.to === 'string' ? route.query.to : '/dashboard'
     await router.replace(redirect || '/dashboard')