deps: bump next from 14.2.18 to 15.0.3 in /docs

Bumps [next](https://github.com/vercel/next.js) from 14.2.18 to 15.0.3.
- [Release notes](https://github.com/vercel/next.js/releases)
- [Changelog](https://github.com/vercel/next.js/blob/canary/release.js)
- [Commits](vercel/next.js@v14.2.18...v15.0.3)

---
updated-dependencies:
- dependency-name: next
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <[email protected]>

docs/package.json

@@ -22,7 +22,7 @@
     "date-fns": "^4.1.0",
     "framer-motion": "^11.5.4",
     "glob": "^11.0.0",
-    "next": "^14.2.5",
+    "next": "^15.0.3",
     "react": "^18.3.1",
     "react-dom": "^18.3.1",
     "react-icons": "^5.2.1",