Bump next from 16.2.2 to 16.2.6 in /admin

Bumps [next](https://github.com/vercel/next.js) from 16.2.2 to 16.2.6.
- [Release notes](https://github.com/vercel/next.js/releases)
- [Changelog](https://github.com/vercel/next.js/blob/canary/release.js)
- [Commits](vercel/next.js@v16.2.2...v16.2.6)

---
updated-dependencies:
- dependency-name: next
  dependency-version: 16.2.6
  dependency-type: direct:production
...

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

Author: dependabot[bot]

admin/package.json

@@ -17,7 +17,7 @@
     "clsx": "^2.1.1",
     "leaflet": "^1.9.4",
     "lucide-react": "^1.7.0",
-    "next": "16.2.2",
+    "next": "16.2.6",
     "next-themes": "^0.4.6",
     "radix-ui": "^1.4.3",
     "react": "^19.2.4",