feat: implement WebCodecs Opus decode for browser listen

- Add broadcastOpusToWeb to PcmBroadcaster interface for raw Opus packets
- Server broadcasts Opus frames with mode byte (1) + user hash + packet data
- Browser detects packet mode: mode=1 for Opus, mode=0 for legacy PCM
- Implement WebCodecs AudioDecoder for Opus decoding in browser
- Keep existing PCM playback as fallback for compatibility
- Show error if WebCodecs unsupported
- Fixes listen feature under Bun where native Opus decode unavailable

tsconfig.json

@@ -10,7 +10,8 @@
     "outDir": "dist",
     "rootDir": "src",
     "experimentalDecorators": true,
-    "emitDecoratorMetadata": true
+    "emitDecoratorMetadata": true,
+    "jsx": "react-jsx"
   },
   "include": ["src/**/*"],
   "exclude": ["node_modules", "dist"]