docs: add docs for preloadRouteComponents (#9607)

docs/content/1.docs/3.api/3.utils/preload-route-components.md

@@ -0,0 +1,40 @@
+---
+title: "preloadRouteComponents"
+---
+
+# `preloadComponents`
+
+`preloadRouteComponent` allows you to manually preload individual pages in your Nuxt app.
+
+> Preloading routes loads the components of a given route that the user might navigate to in future. This ensures that the components are available earlier and less likely to block the navigation, improving performance.
+
+::alert
+Nuxt already automatically preloads the necessary routes if you're using the `NuxtLink` component.
+::
+::ReadMore{link="/docs/api/components/nuxt-link"}
+::
+
+## Example
+
+Preload a route when using `navigateTo`.
+
+```ts
+// we don't await this async function, to avoid blocking rendering
+// this component's setup function
+preloadRouteComponents('/dashboard')
+
+const submit = async () => {
+  const results = await $fetch('/api/authentication')
+
+  if (results.token) {
+    await navigateTo('/dashboard')
+  }
+}
+```
+
+::ReadMore{link="/docs/api/composables/navigate-to"}
+::
+
+::alert{icon=👉}
+Currently, on server, `preloadRouteComponents` will have no effect.
+::