Major Changes:
- Reorganized commands into logical groups (service, ups, group)
- Added new subcommand structure:
- nupst service <enable|disable|start|stop|restart|status|logs|start-daemon>
- nupst ups <add|edit|remove|list|test>
- nupst group <add|edit|remove|list>
- nupst config [show]
- Added --version/-v flag support
- Added restart subcommand for service
- Added command aliases (ls, rm)
- Renamed delete() to remove() in handlers
- Maintained backward compatibility with deprecation warnings
- Updated all help messages to reflect new structure
- Added showVersion(), showServiceHelp(), showUpsHelp() methods
- Fixed readline imports to use node:readline
Breaking Changes:
- Old command format (e.g. 'nupst add') is deprecated
- Users should migrate to new format (e.g. 'nupst ups add')
- Backward compatibility maintained with warnings for now