chore(deps-dev): bump @vitejs/plugin-react in /frontend

Bumps [@vitejs/plugin-react](https://github.com/vitejs/vite-plugin-react/tree/HEAD/packages/plugin-react) from 5.1.4 to 6.0.0.
- [Release notes](https://github.com/vitejs/vite-plugin-react/releases)
- [Changelog](https://github.com/vitejs/vite-plugin-react/blob/main/packages/plugin-react/CHANGELOG.md)
- [Commits](https://github.com/vitejs/vite-plugin-react/commits/plugin-react@6.0.0/packages/plugin-react)

---
updated-dependencies:
- dependency-name: "@vitejs/plugin-react"
  dependency-version: 6.0.0
  dependency-type: direct:development
  update-type: version-update:semver-major
...

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

frontend/package.json

@@ -46,7 +46,7 @@
     "@types/node": "^25.4.0",
     "@types/react": "^19.2.14",
     "@types/react-dom": "^19.2.3",
-    "@vitejs/plugin-react": "^5.1.4",
+    "@vitejs/plugin-react": "^6.0.0",
     "eslint": "^10.0.3",
     "eslint-plugin-react-hooks": "^7.0.1",
     "eslint-plugin-react-refresh": "^0.5.2",