fix: add client-side validation to portal login form

Add requiredValidator and emailValidator rules to the portal login
form, matching the organizer app login. Empty fields and invalid
email format are now caught before the API call.

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

apps/portal/src/pages/login.vue

@@ -3,6 +3,8 @@ import authV1BottomShape from '@images/svg/auth-v1-bottom-shape.svg?raw'
 import authV1TopShape from '@images/svg/auth-v1-top-shape.svg?raw'
 import { VNodeRenderer } from '@layouts/components/VNodeRenderer'
 import { themeConfig } from '@themeConfig'
+import { requiredValidator, emailValidator } from '@core/utils/validators'
+import { VForm } from 'vuetify/components/VForm'
 import { useAuthStore } from '@/stores/useAuthStore'
 import { usePortalStore } from '@/stores/usePortalStore'
 import { apiClient } from '@/lib/axios'
@@ -27,6 +29,7 @@ const form = ref({
   password: '',
 })
 
+const refVForm = ref<VForm>()
 const isPasswordVisible = ref(false)
 const errorMessage = ref('')
 const isSubmitting = ref(false)
@@ -50,6 +53,9 @@ function mapLoginErrorMessage(message: string | undefined): string {
 }
 
 async function onSubmit(): Promise<void> {
+  const { valid } = await refVForm.value!.validate()
+  if (!valid) return
+
   errorMessage.value = ''
   isSubmitting.value = true
 
@@ -209,7 +215,10 @@ function onMfaCancelled() {
             {{ errorMessage }}
           </VAlert>
 
-          <VForm @submit.prevent="onSubmit">
+          <VForm
+            ref="refVForm"
+            @submit.prevent="onSubmit"
+          >
             <VRow>
               <VCol cols="12">
                 <AppTextField
@@ -219,6 +228,7 @@ function onMfaCancelled() {
                   type="email"
                   placeholder="je@email.nl"
                   autocomplete="email"
+                  :rules="[requiredValidator, emailValidator]"
                 />
               </VCol>
 
@@ -229,6 +239,7 @@ function onMfaCancelled() {
                   placeholder="············"
                   :type="isPasswordVisible ? 'text' : 'password'"
                   autocomplete="current-password"
+                  :rules="[requiredValidator]"
                   :append-inner-icon="isPasswordVisible ? 'tabler-eye-off' : 'tabler-eye'"
                   @click:append-inner="isPasswordVisible = !isPasswordVisible"
                 />