docs: integrate @nuxt/ui-pro (#739)

Co-authored-by: Pooya Parsa <pooya@pi0.io>
Co-authored-by: Florent Delerue <florentdelerue@hotmail.com>
Co-authored-by: Sébastien Chopin <seb@nuxt.com>

docs/error.vue

@@ -1,6 +1,6 @@
 <template>
   <div>
-    <Header />
+    <Header :links="links" />
 
     <UContainer>
       <UMain>
@@ -11,7 +11,7 @@
     </UContainer>
 
     <ClientOnly>
-      <LazyUDocsSearch :files="files" :navigation="navigation" />
+      <LazyUDocsSearch :files="files" :navigation="navigation" :links="links" />
     </ClientOnly>
 
     <UNotifications />
@@ -45,6 +45,54 @@ const navigation = computed(() => {
   return branch.value?.name === 'dev' ? dev : main
 })
 
+const links = computed(() => {
+  return [{
+    label: 'Documentation',
+    icon: 'i-heroicons-book-open',
+    to: `${branch.value?.name === 'dev' ? '/dev' : ''}/getting-started`
+  }, {
+    label: 'Playground',
+    icon: 'i-simple-icons-stackblitz',
+    to: '/playground'
+  }, {
+    label: 'Roadmap',
+    icon: 'i-heroicons-academic-cap',
+    to: '/roadmap'
+  }, {
+    label: 'Pro',
+    icon: 'i-heroicons-square-3-stack-3d',
+    to: '/pro',
+    children: [{
+      label: 'Features',
+      to: '/pro#features',
+      exactHash: true,
+      icon: 'i-heroicons-beaker',
+      description: 'Discover all the features of Nuxt UI Pro.'
+    }, {
+      label: 'Pricing',
+      to: '/pro#pricing',
+      exactHash: true,
+      icon: 'i-heroicons-credit-card',
+      description: 'A simple pricing, for solo developers or teams.'
+    }, {
+      label: 'Guide',
+      to: '/pro/guide',
+      icon: 'i-heroicons-book-open',
+      description: 'Learn how to use Nuxt UI Pro in your app.'
+    }, {
+      label: 'Components',
+      to: '/pro/components',
+      icon: 'i-heroicons-cube-transparent',
+      description: 'Discover all the components available in Nuxt UI Pro.'
+    }]
+  }, {
+    label: 'Releases',
+    icon: 'i-heroicons-rocket-launch',
+    to: 'https://github.com/nuxt/ui/releases',
+    target: '_blank'
+  }]
+})
+
 // Provide
 
 provide('navigation', navigation)