Add special comment to indicate the fork

Author: eps1lon

packages/next/src/server/lib/router-utils/typegen.ts

@@ -871,7 +871,7 @@ export function generateValidatorFileStrict(
       ? `import type { ${nextTypes.join(', ')} } from "next/types.js"\n`
       : ''
 
-  return `// This file is generated automatically by Next.js
+  return `// This file is generated automatically by Next.js with experimental.strictRouteTypes
 // Do not edit this file manually
 // This file validates that all pages and layouts export the correct types