Bump react and @types/react in /frontend

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

Updates `react` from 18.3.1 to 19.2.3
- [Release notes](https://github.com/facebook/react/releases)
- [Changelog](https://github.com/facebook/react/blob/main/CHANGELOG.md)
- [Commits](https://github.com/facebook/react/commits/v19.2.3/packages/react)

Updates `@types/react` from 18.3.27 to 19.2.8
- [Release notes](https://github.com/DefinitelyTyped/DefinitelyTyped/releases)
- [Commits](https://github.com/DefinitelyTyped/DefinitelyTyped/commits/HEAD/types/react)

---
updated-dependencies:
- dependency-name: react
  dependency-version: 19.2.3
  dependency-type: direct:production
  update-type: version-update:semver-major
- dependency-name: "@types/react"
  dependency-version: 19.2.8
  dependency-type: direct:development
  update-type: version-update:semver-major
...

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

Author: dependabot[bot]

frontend/package-lock.json

@@ -20,7 +20,7 @@
     "date-fns": "^3.0.0",
     "framer-motion": "^11.0.0",
     "next": "^14.2.35",
-    "react": "^18.3.0",
+    "react": "^19.2.3",
     "react-dom": "^18.3.0",
     "react-markdown": "^10.1.0",
     "react-syntax-highlighter": "^15.5.0",
@@ -35,7 +35,7 @@
   },
   "devDependencies": {
     "@types/node": "^20.11.0",
-    "@types/react": "^18.2.0",
+    "@types/react": "^19.2.8",
     "@types/react-dom": "^18.2.0",
     "@types/react-syntax-highlighter": "^15.5.4",
     "autoprefixer": "^10.4.0",