New CLI helpers
Added support for:
script/run --list-input-devices
script/run --list-output-devices
These code paths:
Initialize just enough of the audio stack to enumerate devices.
Print a clean, human-readable list of input/output devices (including PipeWire / PulseAudio virtual devices like Echo-Cancel Source and pipewire/echo-cancel-sink).
Exit cleanly with status 0 instead of trying to start the full LVA process afterward (fixing the previous CalledProcessError when --list-output-devices was used).
Behavior change
__main__.py now treats the “list devices” modes as early-exit utility modes, not “run LVA and then also print devices”.
This makes it practical to use these commands in setup docs and shell scripts.