Upgrade ESLint to v9 to fix Vercel deployment

Updated ESLint from 8.57.1 to 9.39.1 to resolve peer dependency conflict with eslint-config-next@16.0.3 which requires ESLint >=9.0.0.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

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.