test(issue-18): acknowledge with started in the remaining working-agent scenarios; refresh the subscriber help capture

T1-14 and T1-20 model an agent that goes `working` and completes late. Under
the liveness contract an agent that never publishes `started` is a delivery
failure, so the watcher threads now acknowledge (non-blocking: the record
lands in events.log before the wire publish) and the late completion is
honoured inside the K x N grace as before. help-job_subscriber.txt records
the intended --ack-timeout option.

Full suite at 66f23c7: 888 passed, 3 failed (these), 0 leaked daemons.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01VCgu9Fa9iT7TbJUSzdq4Ff

tests/fixtures/issue_5/phase1/help-job_subscriber.txt

@@ -1,5 +1,6 @@
 usage: job_subscriber.py [-h] (--job JOB | --wait-any) [--timeout TIMEOUT]
-                         [--idle-timeout IDLE_TIMEOUT] [--expect-retention]
+                         [--idle-timeout IDLE_TIMEOUT]
+                         [--ack-timeout ACK_TIMEOUT] [--expect-retention]
                          [--expect-dispatch-token EXPECT_DISPATCH_TOKEN]
                          [--attempt-id ATTEMPT_ID]
                          [--registry-dir REGISTRY_DIR] [--remote] [-v]
@@ -15,6 +16,10 @@ optional arguments:
   --idle-timeout IDLE_TIMEOUT
                         max seconds with no new event (default:
                         job.idle_timeout_sec or 120)
+  --ack-timeout ACK_TIMEOUT
+                        extra idle budget before the first event, for the
+                        injection to produce `started` (default:
+                        job.ack_timeout_sec; Issue #18)
   --expect-retention    warn if no retained terminal event arrives promptly
   --expect-dispatch-token EXPECT_DISPATCH_TOKEN
                         expected dispatch token for CAS verification

tests/test_issue6_fail_closed.py

@@ -522,6 +522,34 @@ def test_t3_3_runner_delegate_job_session_busy_retry(tmp_path, monkeypatch):
     assert jid == "jid_busy_2"
 
 
+def _publish_started_for_registered_job(reg_dir, cwd, env=None):
+    """Issue #18: a working agent that never publishes `started` is a delivery
+    failure (rc 1) under the liveness contract. The R1 re-observation cases
+    below are about an agent that *did* start and then went silent, so the
+    watcher threads acknowledge the job the way the injected command does."""
+    deadline = time.time() + 20
+    while time.time() < deadline:
+        files = list(Path(reg_dir).glob("*.json"))
+        if files:
+            jid = files[0].stem
+            tok = json.loads(files[0].read_text()).get("dispatch_token") or ""
+            args = [sys.executable, str(SKILLS / "multi-agent-mux-delegate-job" / "scripts" / "publish_event.py"),
+                    "--registry-dir", str(reg_dir), "--job", jid, "--event", "started", "--attempts", "1"]
+            if tok:
+                args += ["--expect-dispatch-token", tok]
+            run_env = dict(os.environ)
+            run_env.update(env or {})
+            # Fire and forget: the record lands in events.log before the wire
+            # publish, and blocking here on the broker ACK (seconds) would
+            # delay the scenario steps that follow in the watcher thread.
+            subprocess.Popen(args, stdout=subprocess.DEVNULL, stderr=subprocess.DEVNULL,
+                             cwd=str(cwd), env=run_env)
+            return jid
+        time.sleep(0.1)
+    return None
+
+
+
 # ---------------------------------------------------------------------------
 # T1-14: R1 working 중 subscriber 타임아웃 -> 디스크 completed 재관측 수용 (rc=0)
 # ---------------------------------------------------------------------------
@@ -547,6 +575,7 @@ def test_t1_14_working_agent_reobserve_completed(tmp_path, mock_herdr):
                 if any("agent" in c and "prompt" in c for c in st.get("calls", [])):
                     st["agents"]["agt_w1"]["agent_status"] = "working"
                     state_file.write_text(json.dumps(st, indent=2))
+                    _publish_started_for_registered_job(reg_dir, tmp_path)  # Issue #18: acknowledge
                     break
             except Exception:
                 pass
@@ -603,29 +632,6 @@ def test_t1_14_working_agent_reobserve_completed(tmp_path, mock_herdr):
     assert len(agent_gets) >= 1, "R1 loop must query agent get"
 
 
-def _publish_started_for_registered_job(reg_dir, cwd, env=None):
-    """Issue #18: a working agent that never publishes `started` is a delivery
-    failure (rc 1) under the liveness contract. The R1 re-observation cases
-    below are about an agent that *did* start and then went silent, so the
-    watcher threads acknowledge the job the way the injected command does."""
-    deadline = time.time() + 20
-    while time.time() < deadline:
-        files = list(Path(reg_dir).glob("*.json"))
-        if files:
-            jid = files[0].stem
-            tok = json.loads(files[0].read_text()).get("dispatch_token") or ""
-            args = [sys.executable, str(SKILLS / "multi-agent-mux-delegate-job" / "scripts" / "publish_event.py"),
-                    "--registry-dir", str(reg_dir), "--job", jid, "--event", "started", "--attempts", "1"]
-            if tok:
-                args += ["--expect-dispatch-token", tok]
-            run_env = dict(os.environ)
-            run_env.update(env or {})
-            subprocess.run(args, capture_output=True, text=True, cwd=str(cwd), env=run_env, timeout=60)
-            return jid
-        time.sleep(0.1)
-    return None
-
-
 # ---------------------------------------------------------------------------
 # T1-15: R1 working 고정 + 미발행 -> Issue #18: K×N 후 rc=2 error (working 은 진단일 뿐)
 # ---------------------------------------------------------------------------
@@ -886,6 +892,7 @@ def test_t1_20_loop_worker_late_completed_continues_to_reviewer(tmp_path, mock_h
                 if any("agent" in c and "prompt" in c for c in st.get("calls", [])):
                     st["agents"]["agt_worker"]["agent_status"] = "working"
                     state_file.write_text(json.dumps(st, indent=2))
+                    _publish_started_for_registered_job(reg_dir, tmp_path)  # Issue #18: acknowledge
                     break
             except Exception:
                 pass