Bump the mdx group in /frontend with 2 updates

Bumps the mdx group in /frontend with 2 updates: [@mdx-js/react](https://github.com/mdx-js/mdx/tree/HEAD/packages/react) and [@next/mdx](https://github.com/vercel/next.js/tree/HEAD/packages/next-mdx).


Updates `@mdx-js/react` from 3.0.1 to 3.1.0
- [Release notes](https://github.com/mdx-js/mdx/releases)
- [Changelog](https://github.com/mdx-js/mdx/blob/main/changelog.md)
- [Commits](https://github.com/mdx-js/mdx/commits/3.1.0/packages/react)

Updates `@next/mdx` from 14.2.4 to 15.1.6
- [Release notes](https://github.com/vercel/next.js/releases)
- [Changelog](https://github.com/vercel/next.js/blob/canary/release.js)
- [Commits](https://github.com/vercel/next.js/commits/v15.1.6/packages/next-mdx)

---
updated-dependencies:
- dependency-name: "@mdx-js/react"
  dependency-type: direct:production
  update-type: version-update:semver-minor
  dependency-group: mdx
- dependency-name: "@next/mdx"
  dependency-type: direct:production
  update-type: version-update:semver-major
  dependency-group: mdx
...

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

frontend/package.json

@@ -19,13 +19,13 @@
     "@emotion/styled": "^11.14.0",
     "@fontsource/pacifico": "^5.0.13",
     "@mdx-js/loader": "^3.1.0",
-    "@mdx-js/react": "^3.0.1",
+    "@mdx-js/react": "^3.1.0",
     "@mui/icons-material": "6.4.2",
     "@mui/lab": "6.0.0-beta.25",
     "@mui/material": "6.4.2",
     "@mui/material-nextjs": "6.4.2",
     "@mui/x-date-pickers": "7.25.0",
-    "@next/mdx": "^14.2.4",
+    "@next/mdx": "^15.1.6",
     "@rjsf/core": "5.24.2",
     "@rjsf/mui": "5.24.2",
     "@rjsf/utils": "5.24.2",