feat: separate ADC channels from EMG into dedicated LSL stream

- Channels partitioned by name: 'ADC*' prefix -> ADC stream, rest -> EMG stream
- New 'OpenEphys_ADC' LSL outlet with proper ADC channel labels
- GUI shows ADC stream name field, channel breakdown after connect
- CLI prints EMG/ADC channel lists, --adc-stream-name arg

Author: Jshulgach