## Why
Enabled rollout tracing could silently fail to initialize, and a terminal task status did not establish whether all recording had finished. Trace consumers need to distinguish a complete recording from a partial bundle, including when a task is interrupted.
## What changed
- Fail thread startup or resume if an enabled recorder cannot initialize, while cleaning up session resources.
- Stop recording after the first write or serialization failure and preserve that failure across shared producers.
- Append a closing record when the last writer handle is released without recording errors. Expose `recording_complete` in `state.json` independently of task success, and mark submission-channel closure as an aborted rollout.
- Reject replay logs with missing or reordered events, mismatched rollout IDs, events after completion, or missing or invalid JSON payloads. Valid prefixes remain replayable with `recording_complete` set to `false`.
## Testing
Add coverage for startup failure and recovery, shared-writer failures, finalization after child handles close, incomplete logs, and missing or malformed payloads. Extend session and CLI tests to check recording completion after shutdown, interruption, stream failure, and submission-channel closure.
GitOrigin-RevId: 30d62fa95912fb0442ad1199776d110884066c30
cassirer-openai
297f5e33a5