build(deps): bump next from 15.1.6 to 15.2.4 in /frontend (#75)

Bumps [next](https://github.com/vercel/next.js) from 15.1.6 to 15.2.4.
- [Release notes](https://github.com/vercel/next.js/releases)
- [Changelog](https://github.com/vercel/next.js/blob/canary/release.js)
- [Commits](vercel/next.js@v15.1.6...v15.2.4)

---
updated-dependencies:
- dependency-name: next
  dependency-version: 15.2.4
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

frontend/package.json

@@ -42,7 +42,7 @@
     "lucide-react": "^0.474.0",
     "mjml": "^4.15.3",
     "monaco-editor": "^0.52.2",
-    "next": "15.1.6",
+    "next": "15.2.4",
     "react": "^19.0.0",
     "react-confetti": "^6.2.2",
     "react-day-picker": "8.10.1",