Rescue work from claudomator-work: question/answer, ratelimit, start-next-task

Merges features developed in /site/doot.terst.org/claudomator-work (a
stale clone) into the canonical repo:

- executor: QuestionRegistry for human-in-the-loop answers, rate limit
  detection and exponential backoff retry (ratelimit.go, question.go)
- executor/claude.go: process group isolation (SIGKILL orphans on cancel),
  os.Pipe for reliable stdout drain, backoff retry on rate limits
- api/scripts.go: POST /api/scripts/start-next-task handler
- api/server.go: startNextTaskScript field, answer-question route,
  BroadcastQuestion for WebSocket question events
- web: Cancel/Restart buttons, question banner UI, log viewer, validate
  section, WebSocket auto-connect

All tests pass.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

1 files changed, 140 insertions, 0 deletions

diff --git a/internal/api/server_test.go b/internal/api/server_test.go
index 5094961..af93a77 100644
--- a/internal/api/server_test.go
+++ b/internal/api/server_test.go
@@ -335,3 +335,143 @@ func TestCORS_Headers(t *testing.T) {
 		t.Errorf("OPTIONS status: want 200, got %d", w.Code)
 	}
 }
+
+func TestAnswerQuestion_NoTask_Returns404(t *testing.T) {
+	srv, _ := testServer(t)
+
+	payload := `{"question_id": "toolu_abc", "answer": "blue"}`
+	req := httptest.NewRequest("POST", "/api/tasks/nonexistent/answer", bytes.NewBufferString(payload))
+	req.Header.Set("Content-Type", "application/json")
+	w := httptest.NewRecorder()
+
+	srv.Handler().ServeHTTP(w, req)
+
+	if w.Code != http.StatusNotFound {
+		t.Errorf("status: want 404, got %d; body: %s", w.Code, w.Body.String())
+	}
+}
+
+func TestAnswerQuestion_NoPendingQuestion_Returns404(t *testing.T) {
+	srv, store := testServer(t)
+	createTaskWithState(t, store, "answer-task-1", task.StatePending)
+
+	payload := `{"question_id": "toolu_nonexistent", "answer": "blue"}`
+	req := httptest.NewRequest("POST", "/api/tasks/answer-task-1/answer", bytes.NewBufferString(payload))
+	req.Header.Set("Content-Type", "application/json")
+	w := httptest.NewRecorder()
+
+	srv.Handler().ServeHTTP(w, req)
+
+	if w.Code != http.StatusNotFound {
+		t.Errorf("status: want 404, got %d; body: %s", w.Code, w.Body.String())
+	}
+	var body map[string]string
+	json.NewDecoder(w.Body).Decode(&body)
+	if body["error"] != "no pending question with that ID" {
+		t.Errorf("error: want 'no pending question with that ID', got %q", body["error"])
+	}
+}
+
+func TestAnswerQuestion_WithPendingQuestion_Returns200(t *testing.T) {
+	srv, store := testServer(t)
+	createTaskWithState(t, store, "answer-task-2", task.StateRunning)
+
+	ch := srv.pool.Questions.Register("answer-task-2", "toolu_Q1", []byte(`{}`))
+
+	go func() {
+		payload := `{"question_id": "toolu_Q1", "answer": "red"}`
+		req := httptest.NewRequest("POST", "/api/tasks/answer-task-2/answer", bytes.NewBufferString(payload))
+		req.Header.Set("Content-Type", "application/json")
+		w := httptest.NewRecorder()
+		srv.Handler().ServeHTTP(w, req)
+
+		if w.Code != http.StatusOK {
+			t.Errorf("status: want 200, got %d; body: %s", w.Code, w.Body.String())
+		}
+	}()
+
+	answer := <-ch
+	if answer != "red" {
+		t.Errorf("answer: want 'red', got %q", answer)
+	}
+}
+
+func TestAnswerQuestion_MissingQuestionID_Returns400(t *testing.T) {
+	srv, store := testServer(t)
+	createTaskWithState(t, store, "answer-task-3", task.StateRunning)
+
+	payload := `{"answer": "blue"}`
+	req := httptest.NewRequest("POST", "/api/tasks/answer-task-3/answer", bytes.NewBufferString(payload))
+	req.Header.Set("Content-Type", "application/json")
+	w := httptest.NewRecorder()
+
+	srv.Handler().ServeHTTP(w, req)
+
+	if w.Code != http.StatusBadRequest {
+		t.Errorf("status: want 400, got %d", w.Code)
+	}
+}
+
+func TestHandleStartNextTask_Success(t *testing.T) {
+	dir := t.TempDir()
+	script := filepath.Join(dir, "start-next-task")
+	if err := os.WriteFile(script, []byte("#!/bin/sh\necho 'claudomator start abc-123'\n"), 0755); err != nil {
+		t.Fatal(err)
+	}
+
+	srv, _ := testServer(t)
+	srv.startNextTaskScript = script
+
+	req := httptest.NewRequest("POST", "/api/scripts/start-next-task", nil)
+	w := httptest.NewRecorder()
+	srv.Handler().ServeHTTP(w, req)
+
+	if w.Code != http.StatusOK {
+		t.Fatalf("want 200, got %d; body: %s", w.Code, w.Body.String())
+	}
+	var body map[string]interface{}
+	json.NewDecoder(w.Body).Decode(&body)
+	if body["output"] != "claudomator start abc-123\n" {
+		t.Errorf("unexpected output: %v", body["output"])
+	}
+	if body["exit_code"] != float64(0) {
+		t.Errorf("unexpected exit_code: %v", body["exit_code"])
+	}
+}
+
+func TestHandleStartNextTask_NoTask(t *testing.T) {
+	dir := t.TempDir()
+	script := filepath.Join(dir, "start-next-task")
+	if err := os.WriteFile(script, []byte("#!/bin/sh\necho 'No task to start.'\n"), 0755); err != nil {
+		t.Fatal(err)
+	}
+
+	srv, _ := testServer(t)
+	srv.startNextTaskScript = script
+
+	req := httptest.NewRequest("POST", "/api/scripts/start-next-task", nil)
+	w := httptest.NewRecorder()
+	srv.Handler().ServeHTTP(w, req)
+
+	if w.Code != http.StatusOK {
+		t.Fatalf("want 200, got %d; body: %s", w.Code, w.Body.String())
+	}
+	var body map[string]interface{}
+	json.NewDecoder(w.Body).Decode(&body)
+	if body["output"] != "No task to start.\n" {
+		t.Errorf("unexpected output: %v", body["output"])
+	}
+}
+
+func TestHandleStartNextTask_ScriptNotFound(t *testing.T) {
+	srv, _ := testServer(t)
+	srv.startNextTaskScript = "/nonexistent/start-next-task"
+
+	req := httptest.NewRequest("POST", "/api/scripts/start-next-task", nil)
+	w := httptest.NewRecorder()
+	srv.Handler().ServeHTTP(w, req)
+
+	if w.Code != http.StatusInternalServerError {
+		t.Errorf("want 500, got %d; body: %s", w.Code, w.Body.String())
+	}
+}