[Docs] Add qwen image missing doc in user guide (#111)

Signed-off-by: samithuang <285365963@qq.com>

vllm_omni/diffusion/worker/__init__.py

@@ -0,0 +1,7 @@
+# SPDX-License-Identifier: Apache-2.0
+# SPDX-FileCopyrightText: Copyright contributors to the vLLM project
+"""Diffusion worker components."""
+
+from vllm_omni.diffusion.worker.gpu_worker import GPUWorker, WorkerProc
+
+__all__ = ["GPUWorker", "WorkerProc"]