a little outputqueue refactoring

src/dailyai/output_queue.py

@@ -0,0 +1,14 @@
+from enum import Enum
+from dataclasses import dataclass
+
+class FrameType(Enum):
+    AUDIO_FRAME = 1
+    IMAGE_FRAME = 2
+    START_STREAM = 3
+    END_STREAM = 4
+
+
+@dataclass(frozen=True)
+class OutputQueueFrame:
+    frame_type: FrameType
+    frame_data: bytes