Fix upload_checkpoint.py: explicit HF token and repo_type for upload_folder

[Copilot]

upload_folder was missing repo_type="model" and HfApi was initialized without a token, making the script's behavior dependent on whatever token happened to be cached on disk.

Changes

• Explicit token resolution: reads from HF_TOKEN → HUGGING_FACE_HUB_TOKEN → HUGGINGFACE_HUB_TOKEN and passes it directly to HfApi(token=token)
• repo_type="model": added to upload_folder to match the existing create_repo call and be consistent with other scripts in the repo

token = (
    os.environ.get("HF_TOKEN")
    or os.environ.get("HUGGING_FACE_HUB_TOKEN")
    or os.environ.get("HUGGINGFACE_HUB_TOKEN")
)
api = HfApi(token=token)
api.create_repo(args.repo_id, repo_type="model", private=True, exist_ok=True)
api.upload_folder(
    repo_id=args.repo_id,
    folder_path=args.checkpoint_dir,
    repo_type="model",
    commit_message=f"Checkpoint {datetime.datetime.utcnow().isoformat()}Z",
)

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