Closes#1818
The CLI previously only detected and managed systemd user services
(~/.config/systemd/user/), which failed on VPS/server installs where
the gateway runs as a system service (/etc/systemd/system/).
Changes:
- Check both user and system service paths for unit files
- Try user service first, fall back to system service with sudo
- Update isSystemdServiceEnabled to check both locations
- Update readSystemdServiceRuntime to read from both locations
- Update stop/restart to work with both service types
- Add resolveSystemdSystemUnitPathForName helper
This allows 'clawdbot status' to correctly detect system services and
'enableservice management commands to work with either service type.
Add KillMode=process to generated systemd unit file. Without this,
podman's conmon processes (which monitor sandbox containers) block
shutdown since they're children of the gateway process.
This preserves the desired behavior of keeping containers alive
across restarts while preventing systemd from waiting indefinitely.
