fix(update): the monitor is this workspace's exact command line; create/resume take the pane workspace's admission; refusal snapshots compare the registry by rows (Issue #72, review round 3)

- daemon.find_running matches `<bash> <reconcile.sh> --subscribe[ ...]`
  exactly instead of an unanchored, unescaped pgrep regex: another
  workspace's daemon (ws.a vs wsXa) or a process naming the path in an
  argument is no longer signalled by the update. update.sh re-checks which
  PIDs are still the monitor before SIGKILL.
- create and resume (spawn path) take the update admission of every
  installed workspace at or above the pane cwd, not only the control
  root's (lib.sh mam_update_admit_at, lib_py.update target-workspaces --cwd);
  the ~/.local/bin wrapper child drops all of them.
- tests: snapshot() skips the SQLite -wal/-shm and compares the DB by its
  rows (macOS keeps the sidecars and a read rewrites -shm); regression tests
  for the monitor match and for create/resume in another installed
  workspace (marker and lock wait); evidence line refs shifted.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

tests/test_issue72_admission.py

@@ -230,6 +230,51 @@ def test_delegate_submit_waits_for_the_target_workspace_admission_lock(mam_sandb
     assert _no_job(mam_sandbox)
 
 
+def _start_in(sandbox, entry, b, env=None):
+    """create or resume (spawn path) of an agent whose pane cwd is B/sub."""
+    if entry == "create":
+        argv = ["bash", _script(sandbox, "multi-agent-mux-create/scripts/create_session.sh"),
+                "--workspace", str(b / "sub"), "--agent", "claude", "--role", "creator",
+                "--session", "gated-in-b", "--no-onboard"]
+    else:
+        _seed(sandbox, [dict(_row("gated-in-b", status="stopped", agent="agy"),
+                             pane={"cwd": str(b / "sub"), "cmd": "agy"})])
+        argv = ["bash", _script(sandbox, "multi-agent-mux-resume/scripts/resume_session.sh"),
+                "--workspace", str(b / "sub"), "--agent", "agy", "--session", "gated-in-b"]
+    return _run(sandbox, argv, env=env, timeout=300)
+
+
+@pytest.mark.parametrize("entry", ["create", "resume"])
+def test_create_and_resume_take_the_pane_workspace_marker(mam_sandbox, mock_herdr, mock_agents, marker,
+                                                          other_ws, entry):
+    """An agent started in an installed workspace B other than the control root
+    is one B's update counts, so B's marker refuses it too."""
+    marker(True, other_ws)
+    res = _start_in(mam_sandbox, entry, other_ws)
+    assert res.returncode != 0, res.stdout + res.stderr
+    assert "an update of %s is in progress" % other_ws in res.stderr, res.stdout + res.stderr
+    assert json.loads(Path(mock_herdr).read_text())["agents"] == {}, "nothing was spawned"
+
+
+@pytest.mark.parametrize("entry", ["create", "resume"])
+def test_create_and_resume_wait_for_the_pane_workspace_admission_lock(mam_sandbox, mock_herdr, mock_agents,
+                                                                      other_ws, entry):
+    holder = subprocess.Popen([sys.executable, "-c", "import fcntl, sys, time\n"
+                               "f = open(sys.argv[1], 'a'); fcntl.flock(f, fcntl.LOCK_EX)\n"
+                               "print('locked', flush=True); time.sleep(120)",
+                               str(other_ws / ".mam" / "update-admission.lock")],
+                              stdout=subprocess.PIPE, text=True, start_new_session=True)
+    try:
+        assert holder.stdout.readline().strip() == "locked"
+        res = _start_in(mam_sandbox, entry, other_ws, env={"MAM_UPDATE_ADMISSION_WAIT_S": "1"})
+    finally:
+        holder.kill()
+        holder.wait()
+    assert res.returncode != 0, res.stdout + res.stderr
+    assert "an update of %s holds its admission lock" % other_ws in res.stderr, res.stdout + res.stderr
+    assert json.loads(Path(mock_herdr).read_text())["agents"] == {}, "nothing was spawned"
+
+
 @pytest.mark.parametrize("purge", [False, True])
 def test_stop_refuses_and_changes_nothing(mam_sandbox, mock_herdr, marker, purge):
     _seed(mam_sandbox, [_row("gated-stop")])