## What changed
- Add `TurnInputRequest` and typed submission results for atomically starting a turn, steering the active turn, or declining input with a specific reason.
- Expose `start_or_steer_turn`, `start_turn_if_idle`, and `steer_turn` on `CodexThread`, and migrate Core consumers to these APIs.
- Make app-server `turn/start` steer an active regular turn and return that turn's ID. Reject incompatible output schemas and non-steerable turns without applying settings or enqueueing input.
## Testing
- Cover concurrent start-or-steer submissions, accepted and rejected settings updates, output-schema compatibility, idle-start rejection, and app-server steering.
GitOrigin-RevId: dd9b5528d76ec650c019e97af420bc13190ea86a
## Why
`parent_turn_id` identifies the immediate caller of a nested request, but not the
top-level turn that initiated a multi-level chain of work.
## What changed
- Add `root_turn_id` to turn state, submissions, and Responses API metadata.
- Propagate the root through spawned agents, delegated work, review sessions, and
turn-triggering inter-agent messages.
- Omit the root when background work has no user turn or combined input makes the
root ambiguous.
## Testing
Added coverage for nested agent resumes, reviews, mailbox delivery, steered input,
and reserved metadata handling.
GitOrigin-RevId: 60057db2ee81f4efefa946a9f63c74ff98b93929
## What changed
- Add `auto_review_enabled` to serialized turn metadata for regular and review turns.
- Derive the value from approval-policy routing and reserve the metadata key so client-provided metadata cannot override it.
## Testing
- Cover enabled metadata, reserved-key handling, Guardian review requests, and updated compaction request snapshots.
GitOrigin-RevId: 52773e2bf7d4be251f8466332de9f9c9869dd084
## What changed
- Enable `test_sync_tool` for the startup prewarm test.
- Hold the first user-turn response open while Git enrichment completes, then
verify the refreshed workspace metadata on the follow-up request.
GitOrigin-RevId: dd4254fba1ac2f346022988cc21a78648a29556a
## What changed
- Add `StartThreadOptions::new` to provide the standard configuration for a new thread.
- Make `ThreadManager::start_thread` the single thread-start entry point and migrate callers from the previous convenience methods.
- Derive default environment selections when `environments` is `None`, while preserving explicit selections, including an empty list.
GitOrigin-RevId: 8977dc11aed54c5e1215a81eaed2b2cf5fc6087a
## Why
Startup prewarms and Guardian review sessions do not need workspace Git metadata. Collecting it for those requests performs redundant work, while user turns still need a fresh view of the repository.
## What changed
- Add a per-session Git enrichment policy.
- Skip enrichment for startup prewarm, preview, and Guardian review turns.
- Keep fresh enrichment enabled for regular sessions and one-shot delegated turns.
## Testing
- Cover prewarm and Guardian requests omitting workspace metadata while subsequent user turns observe repository changes.
- Cover concurrent repositories and worktrees retaining distinct metadata.
- Verify concurrent enrichment is coalesced and canceled enrichment can be retried.
GitOrigin-RevId: 4a68615288bb568c75f2e487d9c0776e3e80f191
Owen Lin