Card numbers can shift based on USB enumeration order at boot.
Using 'plughw:ArrayUAC10,0' instead of 'plughw:2,0' ensures
the ReSpeaker is found regardless of when it connects.
Fixed by Vixy after power loss shuffled card order 🦊
- Replaced PyAudio with direct ALSA (arecord subprocess)
- Single audio stream feeds both Porcupine and recording buffer
- Fixes device unavailable error when recording after wake word
- Simplified architecture