Add Zone support to Sony SongPal

There is an existing Songpal integration based on python-songpal, but the HA integration currently only supports sound modes. The underlying Python library has additional support for zone commands (among many others). I would like to use the Zone commands as part of an HA automation as my existing universal remote doesn’t support controlling my receiver in that way, but my remote does integrate with HA and can pick up on state changes. I have a Sony receiver that supports these zone commands (tested via the Python library directly), so can provide testing support if needed. Thanks!