feat: add compaction event (#7289)

codex-rs/core/src/rollout/policy.rs

@@ -42,6 +42,7 @@ pub(crate) fn should_persist_event_msg(ev: &EventMsg) -> bool {
         | EventMsg::AgentReasoning(_)
         | EventMsg::AgentReasoningRawContent(_)
         | EventMsg::TokenCount(_)
+        | EventMsg::ContextCompacted(_)
         | EventMsg::EnteredReviewMode(_)
         | EventMsg::ExitedReviewMode(_)
         | EventMsg::UndoCompleted(_)