chore: align ecosystem to Next.js 16.1.6 and v1.6.0, migrate to ESLint 9 Flat Config

next-env.d.ts

@@ -1,6 +1,6 @@
 /// <reference types="next" />
 /// <reference types="next/image-types/global" />
-import "./.next/dev/types/routes.d.ts";
+import './.next/types/routes.d.ts';
 
 // NOTE: This file should not be edited
 // see https://nextjs.org/docs/app/api-reference/config/typescript for more information.