fix(deps): bump next from 15.5.9 to 16.1.1 in /web

Bumps [next](https://github.com/vercel/next.js) from 15.5.9 to 16.1.1.
- [Release notes](https://github.com/vercel/next.js/releases)
- [Changelog](https://github.com/vercel/next.js/blob/canary/release.js)
- [Commits](vercel/next.js@v15.5.9...v16.1.1)

---
updated-dependencies:
- dependency-name: next
  dependency-version: 16.1.1
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

Author: dependabot[bot]

web/package.json

@@ -19,7 +19,7 @@
     "chart.js": "^4.5.1",
     "chartjs-adapter-date-fns": "^3.0.0",
     "date-fns": "^4.1.0",
-    "next": "15.5.9",
+    "next": "16.1.1",
     "prettier": "^3.7.4",
     "pusher-js": "^8.4.0",
     "react": "19.2.3",