- Added API endpoints for Linux setup experience.
  - Device API endpoints for fleetd: `POST /api/fleet/orbit/setup_experience/init` and `POST /api/v1/fleet/device/{token}/setup_experience/status`
  - `PUT /api/v1/fleet/setup_experience/software` and `GET /api/v1/fleet/setup_experience/software` now have a `platform` argument (`linux` or `macos`, defaults to `macos`).