docs: provide example of exposing a pageRef from a child page (#26806)

docs/3.api/1.components/2.nuxt-page.md

@@ -86,6 +86,18 @@ function logFoo () {
 </template>
 ````
 
+````vue [my-page.vue]
+<script setup lang="ts">
+const foo = () => {
+  console.log('foo method called')
+}
+
+defineExpose({
+  foo,
+})
+</script>
+````
+
 ## Custom Props
 
 In addition, `<NuxtPage>` also accepts custom props that you may need to pass further down the hierarchy.