Persist rollout provenance at the same stickiness boundary

When a rollout decision is sticky for an episode, persist the configuration key, revision, and source beside that decision and reuse that exact receipt for every later evaluation. Never fill missing historical provenance from the current process snapshot: a legacy null means “unknown,” not “today’s revision.” Scope the evaluation receipt per item so one stored episode cannot leak its attribution into the next item in a batch. This preserves analytical truth across config changes; it does not retroactively reconstruct records created before provenance existed.

Applies when: A long-lived workflow keeps a cohort assignment across repeated worker runs. Keywords: rollout attribution sticky cohort revision provenance legacy null batch