fix(deps): bump express and @types/express in /frontend

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

Updates `express` from 5.1.0 to 5.2.1
- [Release notes](https://github.com/expressjs/express/releases)
- [Changelog](https://github.com/expressjs/express/blob/master/History.md)
- [Commits](expressjs/express@v5.1.0...v5.2.1)

Updates `@types/express` from 5.0.3 to 5.0.6
- [Release notes](https://github.com/DefinitelyTyped/DefinitelyTyped/releases)
- [Commits](https://github.com/DefinitelyTyped/DefinitelyTyped/commits/HEAD/types/express)

---
updated-dependencies:
- dependency-name: express
  dependency-version: 5.2.1
  dependency-type: direct:production
  update-type: version-update:semver-minor
- dependency-name: "@types/express"
  dependency-version: 5.0.6
  dependency-type: direct:development
  update-type: version-update:semver-patch
...

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

Author: dependabot[bot]