feat: rewrite to use app config and rework docs (#143)

Co-authored-by: Daniel Roe <daniel@roe.dev>
Co-authored-by: Sébastien Chopin <seb@nuxt.com>

docs/components/content/examples/NotificationExampleActions.vue

@@ -0,0 +1,15 @@
+<script setup>
+const toast = useToast()
+
+const actions = ref([{
+  label: 'Action 1',
+  click: () => alert('Action 1 clicked!')
+}, {
+  label: 'Action 2',
+  click: () => alert('Action 2 clicked!')
+}])
+</script>
+
+<template>
+  <UButton label="Show toast" @click="toast.add({ title: 'With actions', actions })" />
+</template>