chore(deps): bump next from 15.3.4 to 15.5.6

Bumps [next](https://github.com/vercel/next.js) from 15.3.4 to 15.5.6.
- [Release notes](https://github.com/vercel/next.js/releases)
- [Changelog](https://github.com/vercel/next.js/blob/canary/release.js)
- [Commits](vercel/next.js@v15.3.4...v15.5.6)

---
updated-dependencies:
- dependency-name: next
  dependency-version: 15.5.6
  dependency-type: direct:production
...

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

Author: dependabot[bot]

package-lock.json

@@ -29,7 +29,7 @@
     "echarts": "^5.6.0",
     "echarts-for-react": "^3.0.2",
     "lucide-react": "^0.525.0",
-    "next": "15.3.4",
+    "next": "15.5.6",
     "next-auth": "^4.24.11",
     "react": "^19.0.0",
     "react-chartjs-2": "^5.3.0",