feat: add compaction event (#7289)

codex-rs/tui/src/chatwidget.rs

@@ -1796,6 +1796,7 @@ impl ChatWidget {
                 self.on_entered_review_mode(review_request)
             }
             EventMsg::ExitedReviewMode(review) => self.on_exited_review_mode(review),
+            EventMsg::ContextCompacted(_) => self.on_agent_message("Context compacted".to_owned()),
             EventMsg::RawResponseItem(_)
             | EventMsg::ItemStarted(_)
             | EventMsg::ItemCompleted(_)