Windows service is reported to be stopped before XNET listener is properly shut down

[aafemt]

A simple logging showed a problem which is most likely the reason for https://groups.google.com/g/firebird-support/c/6YbU_TEmkLE

SD	Tue Jan 20 17:09:54 2026
	Reporting stop

SD	Tue Jan 20 17:09:54 2026
	Stopped.

SD	Tue Jan 20 17:09:54 2026
	XNET connection mutex destructed

As the result when service manager is restarting the service, races between new and old instances may end up in no XNET listener active at all.

TCP may be affected as well, but there the problem is hidden by SO_REUSEADDR.