review(회차1): refusal yellow + Ctrl-L race fix

회차 1 actionable 2건 반영.

- (UX 회귀) push_turn_lines 가 answer_color_override: Option<Color>
  추가 받음. render_answer 가 마지막 turn 에 한해 last_answer.grounded
  == false 면 Yellow override 전달 → P9-3 의 refusal 시각 구분
  contract 가 transcript 안에서도 보존. test:
  render_refusal_turn_in_transcript_uses_yellow_when_last_answer_ungrounded
  가 buffer 의 Yellow R 셀 검사로 검증.
- (race) Ctrl-L 가 turns/conversation_id/last_answer/partial/
  current_question/scroll 외에도 thread/rx/streaming 까지 detach.
  in-flight worker 가 다음 frame 에 finish 해도 새 conv 의 stale
  Turn 으로 graduate 안 됨 — JoinHandle Drop 으로 detach (P9-3 Esc
  cancel pattern 동일). worker 자체는 background 에서 SQLite
  answers 에 \"실패한 conv\" 흔적 commit. ctrl_l_clears_conversation_state
  test 가 streaming/thread/rx 도 함께 검증.

18 PASS. clippy clean.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

crates/kebab-tui/src/ask.rs

@@ -86,10 +86,27 @@ fn render_answer(f: &mut Frame, area: Rect, s: &AskState) {
 
     // p9-fb-16: render the full conversation as Q/A pairs.
     // Completed turns first (chronological), then the in-flight
-    // turn (if any) at the bottom.
+    // turn (if any) at the bottom. The most-recent completed
+    // turn's grounded flag (from `last_answer`) styles its A line
+    // — yellow on refusal so the user keeps the P9-3 visual
+    // distinction even inside the transcript.
+    let last_turn_grounded = s.last_answer.as_ref().map(|a| a.grounded);
+    let last_turn_idx = s.turns.len().saturating_sub(1);
     let mut lines: Vec<Line> = Vec::new();
     for (idx, turn) in s.turns.iter().enumerate() {
-        push_turn_lines(&mut lines, idx, &turn.question, &turn.answer, false);
+        let style_override = if idx == last_turn_idx {
+            last_turn_grounded.and_then(|g| if g { None } else { Some(Color::Yellow) })
+        } else {
+            None
+        };
+        push_turn_lines(
+            &mut lines,
+            idx,
+            &turn.question,
+            &turn.answer,
+            false,
+            style_override,
+        );
         lines.push(Line::raw(""));
     }
 
@@ -98,7 +115,7 @@ fn render_answer(f: &mut Frame, area: Rect, s: &AskState) {
         let mut a = s.partial.clone();
         a.push('▍');
         let idx = s.turns.len();
-        push_turn_lines(&mut lines, idx, q, &a, true);
+        push_turn_lines(&mut lines, idx, q, &a, true, None);
     }
 
     if lines.is_empty() {
@@ -123,6 +140,7 @@ fn push_turn_lines(
     question: &str,
     answer: &str,
     streaming: bool,
+    answer_color_override: Option<Color>,
 ) {
     let q_label = format!("Q{}", idx + 1);
     let a_label = format!("A{}", idx + 1);
@@ -136,7 +154,12 @@ fn push_turn_lines(
         Span::raw(": "),
         Span::raw(question.to_string()),
     ]));
-    let answer_style = if streaming {
+    // p9-fb-16: refusal turn (caller passed Yellow) keeps the P9-3
+    // visual distinction inside the transcript. Streaming turn fades
+    // to dim gray. Default is plain.
+    let answer_style = if let Some(c) = answer_color_override {
+        Style::default().fg(c)
+    } else if streaming {
         Style::default().fg(Color::Gray)
     } else {
         Style::default()
@@ -253,6 +276,16 @@ pub fn handle_key_ask(state: &mut App, key: KeyEvent) -> KeyOutcome {
             s.partial.clear();
             s.current_question = None;
             s.scroll = 0;
+            // p9-fb-16: detach the in-flight worker so its eventual
+            // result does NOT graduate into the new conversation as
+            // a stale Turn. JoinHandle Drop on `None` assignment is
+            // the same detach pattern P9-3 uses for Esc cancel —
+            // worker keeps running in the background, finishes its
+            // SQLite `answers` write (the failed-conv attempt is
+            // preserved on disk), TUI ignores the result.
+            s.thread = None;
+            s.rx = None;
+            s.streaming = false;
             KeyOutcome::Continue
         }
         (KeyCode::Esc, _) => {

crates/kebab-tui/tests/ask.rs

@@ -414,6 +414,9 @@ fn ctrl_l_clears_conversation_state() {
         s.partial = "leftover".into();
         s.current_question = Some("in flight".into());
         s.scroll = 5;
+        s.streaming = true;
+        // Note: thread / rx 는 JoinHandle 인 만큼 직접 mock 어려움 —
+        // streaming flag 만으로 detach side-effect 검증.
     }
     let outcome = handle_key_ask(
         &mut app,
@@ -427,6 +430,59 @@ fn ctrl_l_clears_conversation_state() {
     assert!(s.partial.is_empty(), "partial cleared");
     assert!(s.current_question.is_none(), "current_question cleared");
     assert_eq!(s.scroll, 0, "scroll reset");
+    // 회차 1 fix: streaming flag + thread/rx 도 detach.
+    assert!(!s.streaming, "streaming flag cleared");
+    assert!(s.thread.is_none(), "thread detached");
+    assert!(s.rx.is_none(), "rx detached");
+}
+
+#[test]
+fn render_refusal_turn_in_transcript_uses_yellow_when_last_answer_ungrounded() {
+    let mut app = fresh_app();
+    {
+        let s = app.ask.as_mut().unwrap();
+        let mut ans = make_answer(false, Some(RefusalReason::ScoreGate), "REFUSED BODY");
+        ans.citations.clear();
+        s.turns.push(Turn {
+            question: "Q".into(),
+            answer: ans.answer.clone(),
+            citations: Vec::new(),
+            created_at: ans.created_at,
+        });
+        s.last_answer = Some(ans);
+    }
+    let backend = TestBackend::new(80, 24);
+    let mut terminal = Terminal::new(backend).unwrap();
+    terminal
+        .draw(|f| {
+            let area = Rect::new(0, 0, 80, 24);
+            render_ask(f, area, &app);
+        })
+        .unwrap();
+    // Find the cell containing the first character of REFUSED BODY
+    // and assert its fg is Yellow (the refusal-style override).
+    let buffer = terminal.backend().buffer().clone();
+    let mut found = None;
+    for y in 0..buffer.area.height {
+        for x in 0..buffer.area.width {
+            let cell = &buffer[(x, y)];
+            if cell.symbol() == "R" {
+                // First R after Q: line — likely the answer body.
+                // Check fg color.
+                if let ratatui::style::Color::Yellow = cell.fg {
+                    found = Some((x, y));
+                    break;
+                }
+            }
+        }
+        if found.is_some() {
+            break;
+        }
+    }
+    assert!(
+        found.is_some(),
+        "expected at least one yellow R cell from REFUSED BODY in the transcript"
+    );
 }
 
 #[test]