Bump @eslint/js and @types/eslint__js in /frontend

Bumps [@eslint/js](https://github.com/eslint/eslint/tree/HEAD/packages/js) and [@types/eslint__js](https://github.com/DefinitelyTyped/DefinitelyTyped/tree/HEAD/types/eslint__js). These dependencies needed to be updated together.

Updates `@eslint/js` from 9.20.0 to 9.21.0
- [Release notes](https://github.com/eslint/eslint/releases)
- [Changelog](https://github.com/eslint/eslint/blob/main/CHANGELOG.md)
- [Commits](https://github.com/eslint/eslint/commits/v9.21.0/packages/js)

Updates `@types/eslint__js` from 8.42.3 to 9.14.0
- [Release notes](https://github.com/DefinitelyTyped/DefinitelyTyped/releases)
- [Commits](https://github.com/DefinitelyTyped/DefinitelyTyped/commits/HEAD/types/eslint__js)

---
updated-dependencies:
- dependency-name: "@eslint/js"
  dependency-type: direct:development
  update-type: version-update:semver-minor
- dependency-name: "@types/eslint__js"
  dependency-type: direct:development
  update-type: version-update:semver-major
...

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

frontend/package.json

@@ -46,8 +46,8 @@
     "vuetify": "^3.7.9"
   },
   "devDependencies": {
-    "@eslint/js": "^9.20.0",
-    "@types/eslint__js": "^8.42.3",
+    "@eslint/js": "^9.21.0",
+    "@types/eslint__js": "^9.14.0",
     "@types/js-cookie": "^3.0.6",
     "@types/lodash": "^4.17.15",
     "@types/node": "^22.13.0",