feat(Form): handle @error event (#718)

Co-authored-by: Albert <albert@Alberts-MacBook-Pro.local>
Co-authored-by: Romain Hamel <romain@boilr.io>
Co-authored-by: Benjamin Canac <canacb1@gmail.com>

docs/components/content/examples/FormExampleOnError.vue

@@ -0,0 +1,42 @@
+<script setup lang="ts">
+import type { FormError, FormErrorEvent, FormSubmitEvent } from '#ui/types'
+
+const state = reactive({
+  email: undefined,
+  password: undefined
+})
+
+const validate = (state: any): FormError[] => {
+  const errors = []
+  if (!state.email) errors.push({ path: 'email', message: 'Required' })
+  if (!state.password) errors.push({ path: 'password', message: 'Required' })
+  return errors
+}
+
+async function onSubmit (event: FormSubmitEvent<any>) {
+  // Do something with data
+  console.log(event.data)
+}
+
+async function onError (event: FormErrorEvent) {
+  const element = document.getElementById(event.errors[0].id)
+  element?.focus()
+  element?.scrollIntoView({ behavior: 'smooth', block: 'center' })
+}
+</script>
+
+<template>
+  <UForm :validate="validate" :state="state" @submit="onSubmit" @error="onError">
+    <UFormGroup label="Email" name="email">
+      <UInput v-model="state.email" />
+    </UFormGroup>
+
+    <UFormGroup label="Password" name="password">
+      <UInput v-model="state.password" type="password" />
+    </UFormGroup>
+
+    <UButton type="submit">
+      Submit
+    </UButton>
+  </UForm>
+</template>