Seed steps

A transition can be performed by a seeds work item instead of by hand:

{"step": "review", "from": "open", "to": "reviewed",
 "seed": {"title": "Review the change", "labels": ["review"]},
 "on_abandon": "reject"}

shuttle reconcile --agent <you> (on a timer, or by hand) does two things for every open run:

• For each seed step legal from the run's state, it runs sd create --workflow-run <run> --step <step> --visit <n>. seeds derives the id from that key, so repeating the create returns the same seed. A run that re-enters the state gets a new visit and a new seed.
• It reads the seed with sd show --json. Outcome done advances the run through the step, signed, with the seed id, outcome and close time recorded as evidence. Any other outcome takes on_abandon. With no on_abandon the run is FLAGGED (exit 1) and never advanced silently.

seeds knows nothing about workflows beyond the link field. A missed tick costs one tick, not a stuck run. SHUTTLE_SD names the sd binary; where seeds stores its work is sd's own configuration.