Remove Hugging Face as selectable model path

[seanpmorgan]

Currently, we have bespoke support for passing a Hugging Face model name to ModelScan. While a nice feature, this expands the scope of ModelScan to larger than it needs to be:

1. Why Hugging Face and not other popular OSS model repositories?
2. We don't properly handle edge cases in HF and don't want to sign up to do so (e.g. HF tokens and models that require you to accept ToS)
3. It makes it so an http client library is a core dependency of ModelScan

Since we're still at a 0.x release, we should remove this capability before it is depended on and not properly maintained. Users can easily download models using their own methods (e.g. hugginface_hub, requests, etc. ) and then use ModelScan once it's available on local disk.