docs(VerticalNavigation): add slots examples (#456)

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

docs/components/content/examples/VerticalNavigationExampleBadgeSlot.vue

@@ -0,0 +1,35 @@
+<script setup>
+const links = [{
+  label: '.github',
+  icon: 'i-heroicons-folder-20-solid',
+  badge: 'chore(github): use pnpm 8',
+  time: 'last month'
+}, {
+  label: '.editorconfig',
+  icon: 'i-heroicons-document-solid',
+  badge: 'Initial commit',
+  time: '2 years ago'
+}, {
+  label: '.package.json',
+  icon: 'i-heroicons-document-solid',
+  badge: 'chore(deps): bump',
+  time: '16 hours ago'
+}]
+</script>
+
+<template>
+  <UVerticalNavigation
+    :links="links"
+    class="w-full"
+    :ui="{
+      label: 'truncate relative text-gray-900 dark:text-white flex-initial w-32 text-left'
+    }"
+  >
+    <template #badge="{ link }">
+      <div class="flex-1 flex justify-between relative truncate">
+        <div>{{ link.badge }}</div>
+        <div>{{ link.time }}</div>
+      </div>
+    </template>
+  </UVerticalNavigation>
+</template>