chore(docs): add support for auto-redirect to language-specific docs

docs/docs/.vitepress/theme/Layout.vue

@@ -1,9 +1,17 @@
 <script setup>
 import DefaultTheme from 'vitepress/theme'
-import { onMounted } from 'vue'
+import { inBrowser, useData } from 'vitepress'
+import { watchEffect } from 'vue'
 import './style.scss'
 
 const { Layout } = DefaultTheme
+
+const { lang } = useData()
+watchEffect(() => {
+  if (inBrowser) document.cookie = `nf_lang=${lang.value}; expires=Mon, 1 Jan 2030 00:00:00 UTC; path=/`
+}, {
+  immediate: false,
+})
 </script>
 
 <template>

docs/docs/public/_headers

@@ -0,0 +1,3 @@
+/assets/*
+  cache-control: max-age=31536000
+  cache-control: immutable

docs/docs/public/_redirects

@@ -0,0 +1,2 @@
+/guide/* /en/guide/:splat  302!  Language=en
+/develop/* /en/develop/:splat  302!  Language=en