potential split between CLI and core library

Sources/AudioTeeCore/Output/AudioOutputProtocol.swift

@@ -0,0 +1,9 @@
+import Foundation
+
+/// Protocol for handling audio output in different formats
+public protocol AudioOutputHandler {
+  func handleAudioPacket(_ packet: AudioPacket)
+  func handleMetadata(_ metadata: AudioStreamMetadata)
+  func handleStreamStart()
+  func handleStreamStop()
+}