fix: remove deprecated instrumentationHook (enabled by default in Next.js 15)

next.config.ts

@@ -3,9 +3,6 @@ import type { NextConfig } from "next";
 const nextConfig: NextConfig = {
   /* config options here */
   output: 'standalone',
-  experimental: {
-    instrumentationHook: true,
-  },
 };
 
 export default nextConfig;