[Feat] /v1/images/generations api supports request cancel (#2621)

Signed-off-by: Semmer <semmer@live.cn>

vllm_omni/entrypoints/openai/api_server.py

@@ -1282,7 +1282,8 @@ async def show_available_models(raw_request: Request) -> JSONResponse:
         HTTPStatus.INTERNAL_SERVER_ERROR.value: {"model": ErrorResponse},
     },
 )
-async def generate_images(request: ImageGenerationRequest, raw_request: Request) -> ImageGenerationResponse:
+@with_cancellation
+async def generate_images(request: ImageGenerationRequest, raw_request: Request):
     """Generate images from text prompts using diffusion models.
 
     OpenAI DALL-E compatible endpoint for text-to-image generation.