- **Cancelling a running chat turn through the work ledger now stops it, and chat turns can no longer be replayed into a queue that never runs them (#4799).** `crewship work cancel` (`POST /work-items/{id}/cancel`) on a running chat turn recorded the request and answered "requested", but nothing told the server running the turn, so the agent kept working and writing memory. The server running a chat turn now checks for a cancel request every two seconds, stops the agent process and settles the turn as cancelled from its observed exit. `crewship work replay` on a finished chat turn used to answer 201 and queue a copy that no worker ever picked up, so each replay left an unfinished item holding chat capacity; it is now refused with 409 and an explanation, and nothing is queued. Replay copies created before this fix are not removed automatically; cancel them with `crewship work cancel <id>`.