fix(dashboard): a served profile is not a gateway of its own

Gateway liveness reports a profile the multiplexer serves as running on
the multiplexer's PID (446f6f79a8). The dashboard read that answer as
"this profile runs its own gateway" in two places. multiplexed_profile_refusal
returned None for every served profile, so while a multiplexer was live
(the only time it matters) start/stop were never refused and a restart
was never rewritten to the multiplexer. The /api/status topology listed
one phantom gateway per served profile beside the host.

_has_own_gateway() answers the actual question: a live gateway whose PID
is not the multiplexer serving the profile. The existing lifecycle test
stubbed _check_gateway_running to False, which is what hid it; it now
runs on the real liveness.

hermes_cli/web_server_gateway.py

@@ -158,7 +158,9 @@ def _collect_profile_gateway_topology() -> Dict[str, Any]:
     multiplex = False
     for name, home in homes:
         try:
-            if not _check_gateway_running(home):
+            # A served profile's liveness is the multiplexer's: listing it here showed one phantom
+            # gateway per served profile beside the host.
+            if not (_check_gateway_running(home) if name == "default" else _has_own_gateway(home)):
                 continue
         except Exception:
             continue
@@ -528,6 +530,24 @@ def _profile_is_multiplexed(profile: str) -> bool:
     return named_profile_served_by_running_multiplexer(profile)
 
 
+def _has_own_gateway(profile_dir: Path) -> bool:
+    """A live gateway of the profile's OWN (a ``--force``-started separate one), not the multiplexer that
+    serves it. Gateway liveness reports a served profile as running on the multiplexer's PID (#97120),
+    so reading liveness alone made every served profile look self-hosted and the refusal below never
+    fired while a multiplexer was live, which is the only time it is needed."""
+    from gateway.status import get_running_pid, multiplexer_liveness_for_profile, resolve_gateway_liveness
+    from hermes_cli.profiles import _check_gateway_running
+    if not _check_gateway_running(profile_dir):
+        return False
+    served = multiplexer_liveness_for_profile(profile_dir)
+    if served is None:
+        return True
+    liveness = resolve_gateway_liveness(
+        profile_dir=profile_dir, use_cache=False,
+        pid_probe=lambda path: get_running_pid(path, cleanup_stale=False))
+    return liveness.running and liveness.pid != served[0]
+
+
 def multiplexed_profile_refusal(profile: Optional[str], verb: str) -> Optional[str]:
     """Refusal text for ``gateway start``/``stop`` on a named profile with no gateway of its own (a
     ``--force``-started separate one is managed normally), else None. ``stop`` is refused only when the
@@ -552,8 +572,7 @@ def multiplexed_profile_refusal(profile: Optional[str], verb: str) -> Optional[s
         return standalone_rescan_message(requested)
     if not served and verb != "start":
         return None
-    from hermes_cli.profiles import _check_gateway_running
-    if _check_gateway_running(profile_dir):
+    if _has_own_gateway(profile_dir):
         return None
     if served:
         return (f"The default gateway already serves profile '{requested}' as a multiplexer; "

tests/hermes_cli/test_gateway_multiplex_served_record.py

@@ -227,9 +227,10 @@ def test_dashboard_liveness_ladder_reports_served_profile_running(served_root):
 def test_dashboard_lifecycle_verbs_target_the_multiplexer(served_root, monkeypatch):
     """`gateway restart` for a served profile restarts the multiplexer (a `-p X` child only exits 78 into
     the action log); `start`/`stop` refuse; a profile with its own gateway is managed normally."""
-    from hermes_cli import profiles as profiles_mod
+    from hermes_cli import web_server_gateway
     from hermes_cli.web_server_gateway import _gateway_subcommand, _profile_action_environment, multiplexed_profile_refusal
-    monkeypatch.setattr(profiles_mod, "_check_gateway_running", lambda home: False)
+    # No stub: a served profile's liveness answers "running" on the MULTIPLEXER's pid, and that must
+    # not read as a gateway of its own (stubbing it False hid exactly that).
     # This process's own HERMES_HOME is coder's; the restart child must still run under the DEFAULT
     # home (the multiplexer's) — a bare `gateway restart` here would inherit coder's home and exit 78.
     restart = _gateway_subcommand("coder", "restart")
@@ -239,7 +240,7 @@ def test_dashboard_lifecycle_verbs_target_the_multiplexer(served_root, monkeypat
     assert _gateway_subcommand("other", "restart") == ["-p", "other", "gateway", "restart"]
     assert multiplexed_profile_refusal("other", "stop") is None
     # coder started its own gateway with --force: it is that gateway the verbs address.
-    monkeypatch.setattr(profiles_mod, "_check_gateway_running", lambda home: True)
+    monkeypatch.setattr(web_server_gateway, "_has_own_gateway", lambda profile_dir: True)
     assert _gateway_subcommand("coder", "restart") == ["-p", "coder", "gateway", "restart"]
     assert multiplexed_profile_refusal("coder", "stop") is None
 
@@ -260,10 +261,8 @@ def test_the_multiplexer_restart_names_the_root_even_under_a_sticky_active_profi
     action log says restarted and the multiplexer never was."""
     from pathlib import Path
 
-    from hermes_cli import profiles as profiles_mod
     from hermes_cli.main import _apply_profile_override
     from hermes_cli.web_server_gateway import _gateway_subcommand, _profile_action_environment
-    monkeypatch.setattr(profiles_mod, "_check_gateway_running", lambda home: False)
     monkeypatch.setenv("HERMES_HOME", str(served_root))  # the dashboard runs as the default profile
     (served_root / "active_profile").write_text("coder")
     monkeypatch.setattr(Path, "home", lambda: served_root.parent)
@@ -277,3 +276,13 @@ def test_the_multiplexer_restart_names_the_root_even_under_a_sticky_active_profi
     monkeypatch.setattr("sys.argv", ["hermes", *restart])
     _apply_profile_override()  # what the spawned child does first
     assert os.environ["HERMES_HOME"] == str(served_root)
+
+
+def test_the_topology_lists_a_served_profile_under_the_multiplexer_not_as_its_own_gateway(served_root, monkeypatch):
+    """`/api/status` topology: a served profile's liveness is the multiplexer's, so it is one gateway
+    serving both, not a second gateway entry for `coder` beside it."""
+    from hermes_cli.web_server_gateway import _collect_profile_gateway_topology
+    monkeypatch.setenv("HERMES_HOME", str(served_root))
+    topology = _collect_profile_gateway_topology()
+    assert [g["profile"] for g in topology["gateways"]] == ["default"]
+    assert "coder" in topology["gateways"][0]["served_profiles"]