fix(deps): update dependency next to v15.5.14 [security] (#460)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

frontend-demo/package.json

@@ -29,7 +29,7 @@
     "axios": "^1.7.7",
     "better-react-mathjax": "^2.3.0",
     "formik": "^2.4.6",
-    "next": "15.5.10",
+    "next": "15.5.14",
     "react": "19.2.3",
     "react-dom": "19.2.3",
     "tiny-invariant": "^1.3.3",