[site/build,#64][s]: remove rewrites effort because not working and breaking existing markdown pages (404).

Unfortunately no way to use nextjs rewrites/redirects for what we want: https://nextjs.org/docs/api-reference/next.config.js/redirects or https://nextjs.org/docs/api-reference/next.config.js/rewrites

Why? We want xyz.md => xyz. Unfortunately nextjs regex matching is for the whole path ie. :page(some-regex) => /abc has the some-regex match all of path not the extension. Furthermore there is no way to redirect to a part fragment.

site/next.config.mjs

@@ -22,17 +22,8 @@ const config = {
   webpack: (config, { buildId, dev }) => {
     config.resolve.symlinks = false
     return config
-  }
-}
-
-const rewrites = async () => {
-    return [
-      {
-        source: '/concepts/:page(.md)',
-        destination: '/concepts/:page',
-      },
-    ]
+  },
 }
 
 
-export default withMDX(rewrites(config))
+export default withMDX(config)