Extract persisted history types into a dedicated crate (#37871)

## 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

codex-rs/core-api/Cargo.toml

@@ -21,6 +21,7 @@ codex-config = { workspace = true }
 codex-core = { workspace = true }
 codex-extension-api = { workspace = true }
 codex-home = { workspace = true }
+codex-history = { workspace = true }
 codex-image-generation-extension = { workspace = true }
 codex-exec-server = { workspace = true }
 codex-features = { workspace = true }

codex-rs/core-api/src/lib.rs

@@ -73,6 +73,7 @@ pub use codex_extension_api::UserInstructionsProvider;
 pub use codex_extension_api::empty_extension_registry;
 pub use codex_features::Feature;
 pub use codex_features::Features;
+pub use codex_history::InitialHistory;
 pub use codex_home::CodexHomeUserInstructionsProvider;
 pub use codex_image_generation_extension::install as install_image_generation_extension;
 pub use codex_login::AuthHeaders;
@@ -103,7 +104,6 @@ pub use codex_protocol::models::PermissionProfile;
 pub use codex_protocol::openai_models::ModelPreset;
 pub use codex_protocol::protocol::AskForApproval;
 pub use codex_protocol::protocol::EventMsg;
-pub use codex_protocol::protocol::InitialHistory;
 pub use codex_protocol::protocol::Op;
 pub use codex_protocol::protocol::SessionConfiguredEvent;
 pub use codex_protocol::protocol::SessionSource;