Bump next from 14.2.26 to 15.4.5

Bumps [next](https://github.com/vercel/next.js) from 14.2.26 to 15.4.5.
- [Release notes](https://github.com/vercel/next.js/releases)
- [Changelog](https://github.com/vercel/next.js/blob/canary/release.js)
- [Commits](vercel/next.js@v14.2.26...v15.4.5)

---
updated-dependencies:
- dependency-name: next
  dependency-version: 15.4.5
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

Author: dependabot[bot]

apps/docs/package.json

@@ -25,7 +25,7 @@
     "fast-glob": "^3.3.3",
     "flexsearch": "^0.8.158",
     "js-yaml": "^4.1.0",
-    "next": "^14.2.26",
+    "next": "^15.5.0",
     "next-themes": "^0.2.1",
     "prism-react-renderer": "^2.4.1",
     "react": "^18.3.1",