Fix SSR hydration mismatch causing blank page and static footer

- Remove :key="lang" on Layout (VitePress handles locale reactivity natively)
- Wrap PixelRobots in ClientOnly to avoid SSR/client Date mismatch

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: 2 people

docs/.vitepress/theme/Layout.vue

@@ -1,20 +1,20 @@
 <script setup>
 import DefaultTheme from 'vitepress/theme'
-import { useData } from 'vitepress'
 import LicenseSelector from '../components/LicenseSelector.vue'
 import PixelRobots from '../components/PixelRobots.vue'
 
 const { Layout } = DefaultTheme
-const { lang } = useData()
 </script>
 
 <template>
-  <Layout :key="lang">
+  <Layout>
     <template #home-hero-image>
       <LicenseSelector />
     </template>
     <template #layout-bottom>
-      <PixelRobots />
+      <ClientOnly>
+        <PixelRobots />
+      </ClientOnly>
     </template>
   </Layout>
 </template>