v1.7.1

installer(macos): fix system-wide LaunchDaemon for root installs

A root install wrote UserName/GroupName=root, but macOS has no "root"
group (root's primary group is wheel), so launchd rejected the job with
EX_CONFIG and never started it. Omit both keys for root (a LaunchDaemon
without UserName already runs as root) and, for any other user, set
GroupName to their real primary group instead of the user name.