unstructured

cb55245f - rfctr: extract OCRAgent.get_agent() out of PDF subtree (#2965)

rfctr: extract OCRAgent.get_agent() out of PDF subtree (#2965) **Summary** File-types other than PDF need to use OCR on extracted images. Extract `OCRAgent.get_agent()` such that any file-type partitioner can use it without risking dependency on PDF-only extras.