Bump the nextjs group in /frontend with 3 updates

Bumps the nextjs group in /frontend with 3 updates: [@next/third-parties](https://github.com/vercel/next.js/tree/HEAD/packages/third-parties), [next](https://github.com/vercel/next.js) and [@next/eslint-plugin-next](https://github.com/vercel/next.js/tree/HEAD/packages/eslint-plugin-next).


Updates `@next/third-parties` from 15.2.0 to 15.2.1
- [Release notes](https://github.com/vercel/next.js/releases)
- [Changelog](https://github.com/vercel/next.js/blob/canary/release.js)
- [Commits](https://github.com/vercel/next.js/commits/v15.2.1/packages/third-parties)

Updates `next` from 15.1.7 to 15.2.1
- [Release notes](https://github.com/vercel/next.js/releases)
- [Changelog](https://github.com/vercel/next.js/blob/canary/release.js)
- [Commits](vercel/next.js@v15.1.7...v15.2.1)

Updates `@next/eslint-plugin-next` from 15.1.7 to 15.2.1
- [Release notes](https://github.com/vercel/next.js/releases)
- [Changelog](https://github.com/vercel/next.js/blob/canary/release.js)
- [Commits](https://github.com/vercel/next.js/commits/v15.2.1/packages/eslint-plugin-next)

---
updated-dependencies:
- dependency-name: "@next/third-parties"
  dependency-type: direct:production
  update-type: version-update:semver-patch
  dependency-group: nextjs
- dependency-name: next
  dependency-type: direct:production
  update-type: version-update:semver-minor
  dependency-group: nextjs
- dependency-name: "@next/eslint-plugin-next"
  dependency-type: direct:development
  update-type: version-update:semver-minor
  dependency-group: nextjs
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

frontend/package-lock.json

@@ -13,7 +13,7 @@
     "@mantine/core": "^7.17.0",
     "@mantine/hooks": "^7.16.1",
     "@mantine/notifications": "^7.17.1",
-    "@next/third-parties": "^15.2.0",
+    "@next/third-parties": "^15.2.1",
     "@tabler/icons-react": "^3.30.0",
     "@tailwindcss/typography": "^0.5.16",
     "@vercel/analytics": "^1.5.0",
@@ -22,13 +22,13 @@
     "isomorphic-dompurify": "^2.22.0",
     "jsdom": "^26.0.0",
     "mongodb": "^6.13.1",
-    "next": "15.1.7",
+    "next": "15.2.1",
     "react": "^19.0.0",
     "react-dom": "^19.0.0"
   },
   "devDependencies": {
     "@eslint/eslintrc": "^3",
-    "@next/eslint-plugin-next": "^15.1.7",
+    "@next/eslint-plugin-next": "^15.2.1",
     "@types/node": "^22",
     "@types/react": "^19",
     "@types/react-dom": "^19",