Can't seem to create a new collection

### Product Category

Models

### Question

As per the documentation, I can create model collections within the Models section of Sagemaker under Registered Models. However the "Collection" button that the documentation says should be there isn't. I have also checked boto3 and aws-cli sagemaker and no command exists to interact with models. The only other place I do see models is within the sagemaker SDK. Can you share with me how to actually create collections and heirarchy of collections as described by the documentation?


### Other Details

_No response_

Start with the referenced SageMaker documentation and the Models > Registered Models UI, then compare the documented Collection workflow with the available boto3 and AWS CLI SageMaker commands. Check whether the SageMaker SDK exposes the same operation; done means identifying whether collections are available, documenting the correct creation path, or confirming that the documentation is inaccurate.

Written by the indexing model from the issue text.