`sift extract <file.pdf>` stats the file (refusing over 100 MiB before the
upload), streams it as the POST body with Content-Type application/pdf and the
ContentLength set, and prints the /v1/extract answer exactly as `sift fetch`
prints a PDF URL — same content output, same errors and exitFor codes.
parseExtractOpts reuses splitAroundPositional; extractURL sends only the set
options with mode=digest when a question is given. main.go gains the case and a
help line; README and skill document the command.
Co-Authored-By: ornith-1.5-35b-a3b <ornith-1.5-35b-a3b@llama.cpp.invalid>
kyleandornith-1.5-35b-a3b
3a3a470cd7