## What changed
Add the disabled-by-default `guardian_recorded_items` feature to forward recorded reviewer items and interruptions through the parent's raw-event subscription, preserving reviewer thread and turn IDs without modifying the parent's history or completing its turn.
Emit reviewer items as `rawResponseItem/completed` notifications and interruptions as interrupted `turn/completed` notifications. Mark opted-in reviewer requests with `guardian_recorded_items` metadata.
## Testing
Extend Guardian integration tests to cover reviewer identity, recorded-item metadata replay, concurrent reviewer interruptions, independent parent completion, and behavior without the feature enabled.
GitOrigin-RevId: beb4dbf6c6f2a800a2fbf3cfd11ae174a1382386