Add vLLM-Omni library info to Hugging Face Hub requests (#5381)

Signed-off-by: Harry Mellor <19981378+hmellor@users.noreply.github.com>
Co-authored-by: Hongsheng Liu <liuhongsheng4@huawei.com>
Co-authored-by: Claude Opus 5 (1M context) <noreply@anthropic.com>

vllm_omni/diffusion/models/utils.py

@@ -168,8 +168,8 @@ def _load_json(model_path: str, filename: str, local_files_only: bool = True) ->
         with open(path) as f:
             return json.load(f)
     else:
-        from huggingface_hub import hf_hub_download
+        from vllm_omni.transformers_utils.repo_utils import hf_api
 
-        cached = hf_hub_download(repo_id=model_path, filename=filename)
+        cached = hf_api().hf_hub_download(repo_id=model_path, filename=filename)
         with open(cached) as f:
             return json.load(f)