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/src/session/handlers.rs

@@ -23,6 +23,7 @@ use crate::tasks::UserShellCommandMode;
 use crate::tasks::UserShellCommandTask;
 use crate::tasks::execute_user_shell_command;
 use crate::user_message_admission::UserMessageAdmission;
+use codex_history::RolloutItem;
 use codex_protocol::error::CodexErr;
 use codex_protocol::error::Result as CodexResult;
 use codex_protocol::models::ContentItem;
@@ -40,7 +41,6 @@ use codex_protocol::protocol::RealtimeConversationListVoicesResponseEvent;
 use codex_protocol::protocol::RealtimeVoicesList;
 use codex_protocol::protocol::ReviewDecision;
 use codex_protocol::protocol::ReviewRequest;
-use codex_protocol::protocol::RolloutItem;
 use codex_protocol::protocol::ThreadMemoryMode;
 use codex_protocol::protocol::ThreadRolledBackEvent;
 use codex_protocol::protocol::ThreadSettingsAppliedEvent;