Include completed commentary in the /copy picker (#43846)

## Why

During an active turn, `/copy` could still offer the previous final response even after a new commentary message had completed.

## What changed

Record every completed agent message with non-empty visible Markdown for copying, including commentary. The picker can then offer the latest completed commentary as a whole response and expose its code blocks.

## Testing

Add a regression test and picker snapshot covering completed commentary during an active turn after a previous final response. Verify that selecting “Whole response” copies the commentary and that the picker lists its shell code block.

GitOrigin-RevId: 0ea1d5e3952ccac21f2ee951d482619de82f28e0

codex-rs/tui/src/chatwidget/streaming.rs

@@ -355,9 +355,7 @@ impl ChatWidget {
         } else {
             self.finalize_completed_assistant_message(Some(parsed.visible_markdown.as_str()));
         }
-        if matches!(item.phase, Some(MessagePhase::FinalAnswer) | None)
-            && !parsed.visible_markdown.is_empty()
-        {
+        if !parsed.visible_markdown.is_empty() {
             self.transcript
                 .record_agent_markdown(parsed.visible_markdown.clone(), message);
         }

codex-rs/tui/src/chatwidget/tests/slash_commands.rs

@@ -1840,6 +1840,40 @@ async fn slash_copy_state_tracks_turn_complete_final_reply() {
     );
 }
 
+#[tokio::test]
+async fn slash_copy_picker_uses_completed_commentary_during_active_turn() {
+    let (mut chat, mut rx, _op_rx) = make_chatwidget_manual(/*model_override*/ None).await;
+    complete_turn_with_message(&mut chat, "turn-1", Some("Previous final response"));
+    handle_turn_started(&mut chat, "active");
+    let commentary = "Here is the command:\n\n```sh\necho current\n```";
+    let current_thread_id = chat.thread_id.map(|id| id.to_string()).unwrap_or_default();
+    chat.handle_server_notification(
+        ServerNotification::ItemCompleted(ItemCompletedNotification {
+            thread_id: current_thread_id,
+            turn_id: "active".to_string(),
+            completed_at_ms: 0,
+            item: AppServerThreadItem::AgentMessage {
+                id: "active-commentary".to_string(),
+                text: commentary.to_string(),
+                phase: Some(MessagePhase::Commentary),
+                memory_citation: None,
+                delivery: None,
+                questions: None,
+            },
+        }),
+        /*replay_kind*/ None,
+    );
+    while rx.try_recv().is_ok() {}
+
+    chat.dispatch_command(SlashCommand::Copy);
+    insta::assert_snapshot!(render_bottom_popup(&chat, /*width*/ 80));
+    chat.handle_key_event(KeyEvent::new(KeyCode::Char('1'), KeyModifiers::NONE));
+    assert_eq!(
+        next_copy_selection(&mut rx),
+        (commentary.to_string(), "Whole response".to_string(),)
+    );
+}
+
 #[tokio::test]
 async fn slash_copy_state_tracks_plan_item_completion() {
     let (mut chat, mut rx, _op_rx) = make_chatwidget_manual(/*model_override*/ None).await;

codex-rs/tui/src/chatwidget/tests/snapshots/codex_tui__chatwidget__tests__slash_commands__slash_copy_picker_uses_completed_commentary_during_active_turn.snap

@@ -0,0 +1,10 @@
+---
+source: tui/src/chatwidget/tests/slash_commands.rs
+expression: "render_bottom_popup(&chat, 80)"
+---
+  Copy to clipboard
+
+› 1. Whole response  Here is the command:
+  2. sh code         echo current
+
+  Press enter to confirm or esc to go back

codex-rs/tui/src/chatwidget/transcript.rs

@@ -38,7 +38,7 @@ pub(super) struct TranscriptState {
     pub(super) active_cell_revision: u64,
     /// One bounded entry shared by layout and paint across unchanged active-cell frames.
     pub(super) active_cell_layout: Cell<Option<ActiveCellLayoutCache>>,
-    /// Markdown of the most recently completed agent response for whole-response copying.
+    /// Markdown of the most recently completed agent message for whole-response copying.
     pub(super) last_agent_markdown: Option<String>,
     /// Original source of that response, before display sanitization, for exact block copying.
     pub(super) last_agent_source: Option<String>,