fix: handle gateway Ctrl+C shutdown cleanly

tests/hermes_cli/test_gateway.py

@@ -1,11 +1,58 @@
 """Tests for hermes_cli.gateway."""
 
-from types import SimpleNamespace
+import sys
+from types import ModuleType, SimpleNamespace
 from unittest.mock import patch, call
 
+import pytest
+
 import hermes_cli.gateway as gateway
 
 
+def _install_fake_gateway_run(monkeypatch, start_gateway):
+    module = ModuleType("gateway.run")
+    module.start_gateway = start_gateway
+    monkeypatch.setitem(sys.modules, "gateway.run", module)
+
+
+def test_run_gateway_exits_cleanly_on_keyboard_interrupt(monkeypatch, capsys):
+    calls = []
+
+    def fake_start_gateway(*, replace, verbosity):
+        calls.append((replace, verbosity))
+        return object()
+
+    def fake_asyncio_run(coro):
+        raise KeyboardInterrupt
+
+    _install_fake_gateway_run(monkeypatch, fake_start_gateway)
+    monkeypatch.setattr(gateway.asyncio, "run", fake_asyncio_run)
+
+    gateway.run_gateway()
+
+    out = capsys.readouterr().out
+    assert calls == [(False, 0)]
+    assert "Press Ctrl+C to stop" in out
+    assert "Gateway stopped." in out
+
+
+def test_run_gateway_exits_nonzero_when_start_gateway_reports_failure(monkeypatch):
+    calls = []
+
+    def fake_start_gateway(*, replace, verbosity):
+        calls.append((replace, verbosity))
+        return object()
+
+    _install_fake_gateway_run(monkeypatch, fake_start_gateway)
+    monkeypatch.setattr(gateway.asyncio, "run", lambda coro: False)
+
+    with pytest.raises(SystemExit) as exc_info:
+        gateway.run_gateway(verbose=1, quiet=True, replace=True)
+
+    assert exc_info.value.code == 1
+    assert calls == [(True, None)]
+
+
 class TestSystemdLingerStatus:
     def test_reports_enabled(self, monkeypatch):
         monkeypatch.setattr(gateway, "is_linux", lambda: True)