backstage release v2.22.0

Added

• (agent-platform) The preset chosen under I want to serve is the pool’s serve intent — served through model-manager as the person once the serving stack is ready, the step shows the served model’s timeline, a reload keeps it, Remove clears it in #2439 by @teemow

Full Changelog: https://github.com/giantswarm/backstage/compare/v2.21.3...v2.22.0