review(p9-3): 회차 1 지적 반영

Esc 후 재질문 시 detached prior worker + 새 worker 동시 in-flight 가능
했음. Ollama endpoint 에 두 요청 동시 발사 → 응답 시간 두 배 + stream
혼동. spawn_ask_worker 진입 시 `s.thread.is_some()` 검사 추가, 이전
worker 가 still alive 면 Enter 무시. input bar 의 busy 텍스트 가 세
상태 (streaming / awaiting prior / idle) 분리 표시 — 사용자가 Enter
가 왜 안 먹히는지 즉시 확인.

회귀 테스트 `enter_with_detached_prior_thread_is_blocked` 추가 — never-
ending 더미 thread 를 hand-install 후 Enter no-op 검증, 종료 시 thread
take() 로 leak 명시 (test process 종료 시 OS 가 reap).

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

crates/kebab-tui/tests/ask.rs

@@ -328,6 +328,41 @@ fn explain_toggle_changes_panel_title() {
     );
 }
 
+#[test]
+fn enter_with_detached_prior_thread_is_blocked() {
+    // R1 fix: after Esc, the prior worker is detached (thread still
+    // running, rx cleared, streaming=false). A new Enter must NOT
+    // spawn a second worker against the same Ollama endpoint until
+    // the prior thread finishes.
+    let mut app = fresh_app();
+    {
+        let s = app.ask.as_mut().unwrap();
+        s.input = "another question".into();
+        s.streaming = false;
+        // Simulate a detached prior worker by hand-installing a
+        // never-ending JoinHandle. (We can't easily make a sleeping
+        // thread without timing flakiness; an empty-loop shim works.)
+        s.thread = Some(std::thread::spawn(|| {
+            // Loop until the test drops the JoinHandle's owner via
+            // App going out of scope. is_finished() will report
+            // false until then.
+            loop {
+                std::thread::sleep(std::time::Duration::from_millis(100));
+            }
+        }));
+    }
+    let outcome = handle_key_ask(
+        &mut app,
+        KeyEvent::new(KeyCode::Enter, KeyModifiers::NONE),
+    );
+    // Enter is a no-op while a prior thread is attached.
+    assert_eq!(outcome, KeyOutcome::Continue);
+    let s = app.ask.as_ref().unwrap();
+    assert!(!s.streaming, "no second worker spawned");
+    // Detach so the never-ending thread can be reaped on test exit.
+    let _leaked = app.ask.as_mut().unwrap().thread.take();
+}
+
 #[test]
 fn no_ask_state_returns_to_library() {
     let mut config = Config::defaults();