build(deps): bump next

Bumps the npm_and_yarn group with 1 update in the /apps/client directory: [next](https://github.com/vercel/next.js).


Updates `next` from 15.1.3 to 15.5.15
- [Release notes](https://github.com/vercel/next.js/releases)
- [Changelog](https://github.com/vercel/next.js/blob/canary/release.js)
- [Commits](vercel/next.js@v15.1.3...v15.5.15)

---
updated-dependencies:
- dependency-name: next
  dependency-version: 15.5.15
  dependency-type: direct:production
  dependency-group: npm_and_yarn
...

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

Author: dependabot[bot]

apps/client/package.json

@@ -43,7 +43,7 @@
     "monaco-editor": "^0.52.2",
     "monaco-themes": "^0.4.8",
     "motion": "^11.18.2",
-    "next": "16.2.4",
+    "next": "15.5.15",
     "next-themes": "^0.3.0",
     "qrcode.react": "^4.2.0",
     "react": "19.2.5",