reset method
Reset all bands to flat (0 dB)
Implementation
EqualizerSettings reset() {
final newBands = bands.map((b) => b.copyWith(gain: 0.0)).toList();
return copyWith(
preset: EqualizerPreset.flat,
bands: newBands,
preampGain: 0.0,
bassBoostEnabled: false,
virtualizerEnabled: false,
);
}