cli: use better approach to Windows services (#172679)

Fixes #167741

This eschews the offical Windows service system in favor of registering
into `HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run`.
Unlike services, this can be done without administrative permissions,
does not require the current username/password, and is not blocked by
miscellaneous and mysterious system policies.

Since the process is basically unmanaged by the OS, this requires a
little legwork to start and stop the process when registering and
unregistering.