fix(session): un item.completed tardif n'efface plus le final agent_message Codex — #240

event_supersedes_pending_final ne fait plus annuler le final en attente par
tout événement autre que Heartbeat/RateLimited/turn-progress: seuls un progress
non-turn Started/Delta, un ToolActivity ou un Error annulent. Le buffering
agent_message survive ainsi jusqu'au flush a turn.completed (regréssion
codex_agent_message_survives_late_completed_item_as_final).

crates/infrastructure/src/session/mod.rs

@@ -1385,6 +1385,41 @@ mod tests {
         );
     }
 
+    #[tokio::test]
+    async fn codex_agent_message_survives_late_completed_item_as_final() {
+        let fake = FakeCli::printing(&[
+            r#"{"type":"thread.started","thread_id":"c"}"#,
+            r#"{"type":"turn.started"}"#,
+            r#"{"type":"item.completed","item":{"id":"i0","type":"agent_message","text":"réponse exploitable"}}"#,
+            r#"{"type":"item.completed","item":{"id":"i1","type":"reasoning","text":"post-traitement"}}"#,
+            r#"{"type":"turn.completed","usage":{}}"#,
+        ]);
+        let s = CodexExecSession::new(
+            SessionId::new_random(),
+            fake.command(),
+            "/",
+            None,
+            Vec::new(),
+            Vec::new(),
+            None,
+            None,
+        );
+
+        let events: Vec<_> = s.send("x").await.expect("send").collect();
+        let finals: Vec<_> = events
+            .iter()
+            .filter_map(|event| match event {
+                ReplyEvent::Final { content } => Some(content.as_str()),
+                _ => None,
+            })
+            .collect();
+        assert_eq!(
+            finals,
+            vec!["réponse exploitable"],
+            "a late completed Codex item must not erase the last agent_message"
+        );
+    }
+
     #[tokio::test]
     async fn codex_zero_agent_message_has_no_final() {
         let fake = FakeCli::printing(&[