[Feature]: HF source for custom models should allow local directory

[electroglyph]

What feature would you like to request?

it's fairly standard for anything that takes a hugginface URL/repo name as input to also take a local folder as input

this change would make testing custom models easier.

i can serve a tar.gz locally, or place the model directly into the expected cache location, but this feature would be a bit nicer

Is there any additional information you would like to provide?

No response

[pangwangshu]

Opened a fix for this: #699. `ModelManagement.download_model` now checks whether the `hf` source resolves to an existing local directory before treating it as a HuggingFace repo id — if it does, the directory is used as-is (after validating `model_file`/`additional_files` are present), so `ModelSource(hf="/path/to/local-model")` (or `~/...`) works without publishing to the Hub first.