Add v2 Game Boy sound engine (isolated from v1)

- Authentic DMG-CPU sound chip implementation:
  - 4 Pulse channels with duty cycle control (12.5%, 25%, 50%, 75%)
  - 2 Wave channels with 4-bit wavetables
  - 2 Noise channels with LFSR (7-bit and 15-bit modes)

- GameBoy Colorizer effect chain:
  - Low-pass filter (natural GB rolloff)
  - Bit-crushing (4-bit DAC simulation)
  - Sample rate reduction
  - Saturation and high-pass filter
  - Presets: DMG, GBC, GBA, Clean

- Intelligent MIDI processing:
  - Track analysis and role detection (bass, lead, drums, etc.)
  - Automatic channel mapping to GB channels
  - Chord arpeggiator for polyphony handling
  - GameBoy Arranger for fuller sound

- BitMidi search integration
- Completely isolated from v1 (no changes to src/)

src-v2/index.ts

@@ -0,0 +1,77 @@
+/**
+ * Wario Synth v2 - Main Exports
+ * 
+ * Game Boy-authentic synthesis engine
+ */
+
+// Core Player - Main entry point
+export { GameBoyPlayer } from './core/GameBoyPlayer';
+
+// APU and Channels
+export { GameBoyAPU } from './audio/apu/APU';
+export { PulseChannel } from './audio/apu/PulseChannel';
+export { WaveChannel } from './audio/apu/WaveChannel';
+export { NoiseChannel } from './audio/apu/NoiseChannel';
+
+// Synthesis primitives
+export { 
+  DUTY_PATTERNS,
+  createDutyWave,
+  createAllDutyWaves,
+  getDutyDescription,
+  type DutyIndex
+} from './audio/synthesis/DutyCycle';
+
+export {
+  calculatePulseFrequency,
+  calculateWaveFrequency,
+  calculateNoiseFrequency,
+  midiToStandardFrequency,
+  getFrequencyDeviation
+} from './audio/synthesis/FrequencyCalc';
+
+export {
+  LFSR,
+  generateNoiseBuffer,
+  verifyLFSR,
+  type LFSRMode
+} from './audio/synthesis/LFSR';
+
+export {
+  WaveTable,
+  WAVE_PRESETS,
+  generateTriangleWave,
+  generateSawtoothWave,
+  generateSineWave,
+  generateSquareWave,
+  generateBassWave,
+  generatePadWave,
+  generateLeadWave,
+  type WavePreset,
+  type WaveVolume
+} from './audio/synthesis/WaveTable';
+
+// MIDI Intelligence
+export { TrackAnalyzer, type MIDINote, type MIDITrack } from './audio/midi/TrackAnalyzer';
+export { Arpeggiator, type ArpeggiatorConfig } from './audio/midi/Arpeggiator';
+export { ChannelMapper, type ChannelMapperConfig } from './audio/midi/ChannelMapper';
+
+// Arranger (makes sparse MIDIs sound full like real GB music)
+export { GameBoyArranger, type ArrangerConfig, type ArrangementResult } from './audio/arranger/GameBoyArranger';
+
+// Effects
+export { GameBoyColorizer, type ColorizerConfig } from './audio/effects/GameBoyColorizer';
+
+// Types
+export * from './types';
+
+// Tests
+export {
+  runVerificationTests,
+  createTestChannels,
+  testDutyCycles,
+  testWaveChannel,
+  testNoiseChannel,
+  testCombined,
+  runAllAudioTests
+} from './audio/test/soundTest';