[Frontend] OpenAI-compliant fullduplex /v1/realtime with Qwen3-Omni support (#7285)

Signed-off-by: vraiti <vraiti@redhat.com>

tests/entrypoints/openai_api/test_api_server_guards.py

@@ -58,6 +58,7 @@ from starlette.requests import Request
 from starlette.websockets import WebSocketDisconnect
 from vllm.v1.engine.exceptions import EngineDeadError, EngineGenerateError
 
+from vllm_omni.entrypoints.duplex import openai as duplex_openai
 from vllm_omni.entrypoints.openai import api_server
 from vllm_omni.entrypoints.serve.utils import errors as serve_errors
 
@@ -225,7 +226,6 @@ _MULTISTAGE_APP_STATE_KEYS = {
     "openai_streaming_speech",
     "openai_streaming_video",
     "openai_serving_duplex",
-    "openai_serving_realtime",
     "openai_serving_video",
     "openai_serving_realtime_robot",
     "rl_rollout_serving",
@@ -673,7 +673,7 @@ async def test_realtime_route_defaults_to_configured_duplex_handler(
         async def handle_connection(self) -> None:
             calls.append("legacy")
 
-    monkeypatch.setattr(api_server, "RealtimeConnection", lambda _websocket, _serving: _LegacyConnection())
+    monkeypatch.setattr(duplex_openai, "RealtimeConnection", lambda _websocket, _serving: _LegacyConnection())
     query_params = {} if duplex_query is None else {"duplex": duplex_query}
     websocket = SimpleNamespace(
         app=SimpleNamespace(
@@ -1100,7 +1100,6 @@ async def test_multistage_app_state_key_snapshot(monkeypatch) -> None:
     monkeypatch.setattr(api_server, "OmniOpenAIServingAudioGenerate", _FakeCtor)
     monkeypatch.setattr(api_server, "OmniStreamingSpeechHandler", _FakeCtor)
     monkeypatch.setattr(api_server, "create_streaming_video_handler", lambda **_k: _marker("streaming_video"))
-    monkeypatch.setattr(api_server, "OpenAIServingRealtime", _FakeCtor)
     monkeypatch.setattr(api_server, "OmniOpenAIServingVideo", _FakeCtor)
 
     state = State()