c2071a9724
Adds: - AudioConfig.mode field: 'mono' (default) or 'stereo_4cm' - capture_channels / playback_channels properties for dynamic JACK -i/-o counts - FOCUSRITE_PROFILES dict with focusrite_2i2_3gen entry - AudioSystem.channel_mapping_help() static method - stereo_4cm port auto-connect wiring (4 cable method) - Systemd service content uses dynamic channel counts - Default config YAML includes 'mode: mono' - 11 new tests (31 total pass) - Focusrite 4CM wiring docs in docs/config-audio.md