Use `sounddevice` to simplify audio routing and improve UX

[dam2452]

1. Try switching to [python-sounddevice](https://python-sounddevice.readthedocs.io/en/0.5.1/) instead of virtual audio cables

   • Goal: play and record audio directly in Python, without needing VB-CABLE or any virtual audio devices.
   • This would make setup much easier for users (especially cross-platform).
   • If possible, use sounddevice to make both playback and recording work in all VoiceBreaker modes.

2. Update --verify so it does NOT require two virtual cables

   • Right now, --verify needs a second VB-CABLE (so you can both play and record at once).
   • With sounddevice, maybe we can play the prompt and record the bot's answer from the same device without this extra cable.
   • If it works: remove that extra requirement, and update the README to reflect the simpler setup.

3. Make device selection easier

   • Add a simple script, wizard, or automatic detection for choosing mic and output devices.
   • Show users their available devices and let them pick by name or number.