Extractor yaml files should have --cache / mount options to avoid model re-downloads (and similar)

[yenicelik]

Especially when using larger machine learning models (i.e. from huggingface), mounting a drive to the local huggingface cache will be useful. An optional "mount" parameter in the model yaml file could be a good way to implement this

[yenicelik]

Instead (or in addition to) of an mount option, we could also accept another input file to accept an extension to a Dockerfile (which uses the FROM diptanu/indexify-base-extractor base image)