Bump next from 15.5.4 to 15.5.6 (#336)

Bumps [next](https://github.com/vercel/next.js) from 15.5.4 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@v15.5.4...v15.5.6)

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

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

package.json

@@ -25,7 +25,7 @@
     "javascript-time-ago": "^2.5.11",
     "lucide-react": "^0.544.0",
     "marked": "^16.3.0",
-    "next": "^15.5.4",
+    "next": "^15.5.6",
     "react": "^19.2.0",
     "react-dom": "^19.2.0",
     "react-ga": "^3.3.1",