chore(deps): bump react, react-dom and @types/react in /frontend (#45)

Bumps [react](https://github.com/facebook/react/tree/HEAD/packages/react), [react-dom](https://github.com/facebook/react/tree/HEAD/packages/react-dom) 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 19.0.0
- [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/v19.0.0/packages/react)

Updates `react-dom` from 18.3.1 to 19.0.0
- [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/v19.0.0/packages/react-dom)

Updates `@types/react` from 18.3.12 to 19.0.1
- [Release notes](https://github.com/DefinitelyTyped/DefinitelyTyped/releases)
- [Commits](https://github.com/DefinitelyTyped/DefinitelyTyped/commits/HEAD/types/react)

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

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

frontend/package.json

@@ -19,15 +19,15 @@
     "framer-motion": "^11.13.1",
     "lucide-react": "^0.468.0",
     "mern-auth-backend": "file:..",
-    "react": "^18.3.1",
-    "react-dom": "^18.3.1",
+    "react": "^19.0.0",
+    "react-dom": "^19.0.0",
     "react-router-dom": "^7.0.2",
     "sonner": "^1.7.0",
     "zustand": "^5.0.2"
   },
   "devDependencies": {
     "@eslint/js": "^9.16.0",
-    "@types/react": "^18.3.5",
+    "@types/react": "^19.0.1",
     "@types/react-dom": "^18.3.0",
     "@vitejs/plugin-react": "^4.3.4",
     "autoprefixer": "^10.4.20",