feat(ack): supervise worker liveness after dispatch instead of blind wait

tests/test_ack_worker_probe.py

@@ -0,0 +1,142 @@
+from __future__ import annotations
+
+import contextlib
+import io
+import json
+import sys
+import unittest
+from pathlib import Path
+from unittest import mock
+
+
+REPO_ROOT = Path(__file__).resolve().parents[1]
+ACK_SCRIPTS = REPO_ROOT / "skills" / "ack" / "scripts"
+sys.path.insert(0, str(ACK_SCRIPTS))
+
+import launch_worker  # noqa: E402
+import worker_probe  # noqa: E402
+
+
+def dispatch_show(heartbeat: str | None = None) -> dict:
+    dispatch: dict = {
+        "id": "ctx_dispatch_1",
+        "status": "dispatched",
+        "last_heartbeat_at": heartbeat,
+    }
+    return {"ok": True, "result": {"dispatch": dispatch}}
+
+
+def terminal_read(tail: list[str]) -> dict:
+    return {
+        "ok": True,
+        "result": {
+            "terminal": {
+                "handle": "term_worker_1",
+                "status": "running",
+                "tail": tail,
+            }
+        },
+    }
+
+
+class WorkerProbeClassifyTests(unittest.TestCase):
+    def test_approval_stall_is_detected(self) -> None:
+        result = worker_probe.classify(
+            "Switch to gpt-5.6-luna for lower credit usage? › 1. Switch",
+            None,
+        )
+        self.assertEqual(result["status"], "stall")
+        self.assertEqual(result["stallReason"], "model-switch")
+
+    def test_approve_prompt_is_detected(self) -> None:
+        result = worker_probe.classify(
+            "Allow tool: bash\nRun this command? (y/n)", None
+        )
+        self.assertEqual(result["status"], "stall")
+        self.assertEqual(result["stallReason"], "approval")
+
+    def test_usage_limit_is_detected(self) -> None:
+        result = worker_probe.classify(
+            "You've hit your usage limit. Upgrade to Plus to continue.", None
+        )
+        self.assertEqual(result["status"], "stall")
+        self.assertEqual(result["stallReason"], "usage-limit")
+
+    def test_heartbeat_means_progress_even_without_tail_markers(self) -> None:
+        result = worker_probe.classify(
+            "some unclassified output", "2026-08-23T12:00:00Z"
+        )
+        self.assertEqual(result["status"], "progress")
+        self.assertEqual(result["heartbeatAt"], "2026-08-23T12:00:00Z")
+
+    def test_working_marker_means_running_without_heartbeat(self) -> None:
+        result = worker_probe.classify(["• Working (12s)"], None)
+        self.assertEqual(result["status"], "running")
+
+    def test_welcome_screen_means_not_started(self) -> None:
+        result = worker_probe.classify(
+            ["Welcome to fish, the friendly interactive shell", "Type help"],
+            None,
+        )
+        self.assertEqual(result["status"], "not-started")
+
+    def test_empty_tail_means_not_started(self) -> None:
+        result = worker_probe.classify("", None)
+        self.assertEqual(result["status"], "not-started")
+
+
+class WorkerProbeMainTests(unittest.TestCase):
+    def test_main_emits_single_json_with_progress(self) -> None:
+        with (
+            mock.patch.object(
+                worker_probe,
+                "resolve_executable",
+                return_value=Path("/trusted/orca"),
+            ),
+            mock.patch.object(
+                worker_probe,
+                "run_json",
+                side_effect=[
+                    dispatch_show(heartbeat="2026-08-23T12:00:00Z"),
+                    terminal_read(["Working (5s)"]),
+                ],
+            ),
+        ):
+            buffer = io.StringIO()
+            with contextlib.redirect_stdout(buffer):
+                exit_code = worker_probe.main(
+                    ["--task-id", "task_1", "--terminal", "term_worker_1"]
+                )
+            payload = json.loads(buffer.getvalue())
+        self.assertEqual(exit_code, 0)
+        self.assertEqual(payload["status"], "progress")
+        self.assertEqual(payload["taskId"], "task_1")
+        self.assertEqual(payload["dispatchId"], "ctx_dispatch_1")
+        self.assertEqual(payload["terminal"], "term_worker_1")
+
+    def test_main_reports_unknown_on_probe_failure_without_raising(self) -> None:
+        with (
+            mock.patch.object(
+                worker_probe,
+                "resolve_executable",
+                return_value=Path("/trusted/orca"),
+            ),
+            mock.patch.object(
+                worker_probe,
+                "run_json",
+                side_effect=launch_worker.LaunchError("orca unreachable"),
+            ),
+        ):
+            buffer = io.StringIO()
+            with contextlib.redirect_stdout(buffer):
+                exit_code = worker_probe.main(
+                    ["--task-id", "task_1", "--terminal", "term_worker_1"]
+                )
+            payload = json.loads(buffer.getvalue())
+        self.assertEqual(exit_code, 0)
+        self.assertEqual(payload["status"], "unknown")
+        self.assertIn("probe failed", payload["evidence"])
+
+
+if __name__ == "__main__":
+    unittest.main()