feat(Form): new component (#439)

Co-authored-by: Benjamin Canac <canacb1@gmail.com>

docs/components/content/examples/FormExampleBasic.vue

@@ -0,0 +1,44 @@
+<script setup lang="ts">
+import { ref } from 'vue'
+import type { FormError } from '@nuxthq/ui/dist/runtime/types'
+
+const state = ref({
+  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
+}
+
+const form = ref()
+
+async function submit () {
+  await form.value!.validate()
+  // Do something with state.value
+}
+</script>
+
+<template>
+  <UForm
+    ref="form"
+    :validate="validate"
+    :state="state"
+    @submit.prevent="submit"
+  >
+    <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>