refactor: extract recorder domain types and modules

src/recorder/audioStream.ts

@@ -0,0 +1,26 @@
+import { EndBehaviorType, type VoiceReceiver } from "@discordjs/voice";
+
+export interface AudioStreamHandlers {
+  onPacket: (chunk: Buffer) => void;
+  onEnd: () => void;
+  onError: (error: Error) => void;
+}
+
+export function subscribeToAudioStream(
+  receiver: VoiceReceiver,
+  userId: string,
+  handlers: AudioStreamHandlers,
+): NodeJS.ReadableStream {
+  const audioStream = receiver.subscribe(userId, {
+    end: {
+      behavior: EndBehaviorType.AfterSilence,
+      duration: 3000,
+    },
+  });
+
+  audioStream.on("data", handlers.onPacket);
+  audioStream.on("end", handlers.onEnd);
+  audioStream.on("error", handlers.onError);
+
+  return audioStream;
+}