## What changed
- Wrap response items with optional harness-owned metadata while keeping the persisted response payload shape backward compatible.
- Store compacted-history metadata in an aligned sidecar and reject malformed sidecars.
- Carry metadata through history normalization, compaction, resume, fork, truncation, migration, and rollout recording without sending it to model providers.
## Testing
- Cover legacy rollout compatibility, metadata serialization and validation, compaction retention, and resume/fork reconstruction.
GitOrigin-RevId: 17a6127c9048ff984cb4df4d97c0751a38c29f5f
## What changed
- Add `ResponseItemEnvelope` as the history-owned wrapper for a `ResponseItem`.
- Store envelopes in `ContextManager` while keeping raw-item iteration and consuming APIs for existing callers.
- Preserve envelopes when compaction and history normalization rewrite retained items, and wrap newly synthesized items.
## Testing
- Cover envelope access, mutation, and conversion back to raw response items.
- Cover annotated history replacement and annotated user-message collection for compaction.
GitOrigin-RevId: 3fa2e7bdd981b08cc7aec410c80deccaecdabab4
## What changed
- Add `codex-history` for model-history and persisted-rollout domain types, including `RolloutItem`, `RolloutLine`, `CompactedItem`, and initial/resumed history state.
- Re-export the persisted types from `codex-rollout` and update consumers to use the new crate boundary instead of `codex-protocol`.
- Preserve existing rollout serialization, including legacy numeric compacted-window IDs.
## Testing
- Add `codex-history` tests for rollout JSON round trips, compacted-history compatibility, persisted history modes, and multi-agent version selection.
GitOrigin-RevId: 944daa9297ddd231d3aebbdcb05fff4adf8b4e1b