docs: Add next-i18n-router as a resource for internationalized rout…

…ing (#52344)

### Why?
Many developers are asking how to add internationalized routing in the App Router as it works in the Pages Router. [next-i18n-router](https://www.npmjs.com/package/next-i18n-router) is a very helpful package that fully solves this challenge.

### How?
Unlike the example provided in these Next.js i18n docs, [next-i18n-router](https://www.npmjs.com/package/next-i18n-router) does not require nesting all pages in a `[lang]` dynamic segment. It also allows for the default language to be accessible without a locale prefix in the path (just like in the Pages Router).

It includes locale detection based on the `accept-language` header as recommended in the Next.js docs, as well as support for the `NEXT_LOCALE` cookie to set a user's preferred language (just like in the Pages Router).

docs/02-app/01-building-your-application/01-routing/13-internationalization.mdx

@@ -147,8 +147,9 @@ export default function Root({ children, params }) {
 }
 ```
 
-## Examples
+## Resources
 
 - [Minimal i18n routing and translations](https://github.com/vercel/next.js/tree/canary/examples/app-dir-i18n-routing)
-- [next-intl](https://next-intl-docs.vercel.app/docs/next-13)
-- [next-international](https://github.com/QuiiBz/next-international)
+- [`next-intl`](https://next-intl-docs.vercel.app/docs/next-13)
+- [`next-international`](https://github.com/QuiiBz/next-international)
+- [`next-i18n-router`](https://github.com/i18nexus/next-i18n-router)