fix(gateway): skip ctrl-break wait when signal is rejected

nanobot/gateway/runtime.py

@@ -295,9 +295,16 @@ class GatewayRuntime:
         if ctrl_break is not None:
             # Detached Windows children can reject CTRL_BREAK_EVENT with WinError 87;
             # keep the existing taskkill fallback for that process shape.
-            with suppress(ProcessLookupError, OSError):
+            ctrl_break_sent = False
+            try:
                 os.kill(pid, ctrl_break)
-            if self._wait_for_exit(pid, timeout_s):
+            except ProcessLookupError:
+                return True
+            except OSError:
+                pass
+            else:
+                ctrl_break_sent = True
+            if ctrl_break_sent and self._wait_for_exit(pid, timeout_s):
                 return True
         self._subprocess_run(
             ["taskkill", "/PID", str(pid), "/T"],

tests/gateway/test_runtime.py

@@ -174,6 +174,7 @@ def test_stop_keeps_state_when_process_survives_timeout(tmp_path, monkeypatch):
 
 def test_terminate_windows_falls_back_when_ctrl_break_is_rejected(tmp_path, monkeypatch):
     taskkill_calls: list[dict] = []
+    wait_timeouts: list[int | float] = []
 
     def fake_run(command, **kwargs):
         taskkill_calls.append({"command": command, "kwargs": kwargs})
@@ -193,12 +194,14 @@ def test_terminate_windows_falls_back_when_ctrl_break_is_rejected(tmp_path, monk
     monkeypatch.setattr("nanobot.gateway.runtime.os.kill", fake_kill)
 
     def fake_wait_for_exit(_pid, _timeout_s):
+        wait_timeouts.append(_timeout_s)
         # Simulate a process that only exits after the taskkill fallback runs.
         return bool(taskkill_calls)
 
     monkeypatch.setattr(runtime, "_wait_for_exit", fake_wait_for_exit)
 
     assert runtime._terminate_windows(12345, timeout_s=20) is True
+    assert wait_timeouts == [2]
     assert taskkill_calls == [
         {
             "command": ["taskkill", "/PID", "12345", "/T"],