[Realtime] Emit current (non-beta) OpenAI audio/transcript event names (#7339)

Signed-off-by: Nick Cao <ncao@redhat.com>
Co-authored-by: Claude Sonnet 5 <noreply@anthropic.com>

tests/model_executor/models/personaplex/duplex/test_unified_runtime.py

@@ -61,7 +61,7 @@ def _audio_client(
     frames[:voiced_frames] = 1000
     raw = frames.tobytes()
     event = {
-        "type": "response.audio.delta",
+        "type": "response.output_audio.delta",
         "response_id": "response-1",
         "sample_rate_hz": e2e_driver.SAMPLE_RATE_HZ,
         "metadata": {