The old way to expose the sitemap was to use getServerSideProps in /pages directory. In the /app directory, we got the following approach:

import { MetadataRoute } from 'next'
 
export default function sitemap(): MetadataRoute.Sitemap {
  return [
    {
      url: 'https://acme.com',
      lastModified: new Date(),
    },
    {
      url: 'https://acme.com/about',
      lastModified: new Date(),
    },
    {
      url: 'https://acme.com/blog',
      lastModified: new Date(),
    },
  ]
}

My problem is that I am not actually generating the sitemap, I am getting it from the Strapi as an xml string. I need to pass it to the Next, but there is no string type available, only the MetadataRoute.Sitemap. How do I resolve this?