Improve MIDI search and add browser playback engines.

src/core/MotifEngine.ts

@@ -1,4 +1,4 @@
-import type { NoteEvent, StructuralFeatures, MotifConfig, SynthLayer } from '../types';
+import type { NoteEvent, StructuralFeatures, MotifConfig } from '../types';
 import { MIDIProcessor } from '../midi/MIDIProcessor';
 import { MIDIParser } from '../midi/MIDIParser';
 import { MIDIService } from '../services/MIDIService';
@@ -106,6 +106,12 @@ export class MotifEngine {
     }
   }
 
+  setVolume(volume: number): void {
+    if (this.synthesisEngine) {
+      this.synthesisEngine.setVolume(volume);
+    }
+  }
+
   private generateSyntheticMIDI(songName: string): NoteEvent[] {
     // Generate procedural MIDI based on song name hash
     const hash = this.simpleHash(songName);