Add POST /v1/extract: auth the caller, read the PDF body, hash it, and answer
it on the PDF fetch path exactly as /v1/fetch answers the same PDF by URL. The
hash is the content-addressed cache key ("upload:"+hash under the caller class),
so identical content is extracted once with no TTL or revalidation. The api.go
diff is scoped to the rule-1 changes: the DefaultPDFMaxUpload const, the
PDFMaxUpload Server field, the route, and the two ServeHTTP lines.
Co-Authored-By: ornith-1.5-35b-a3b <ornith-1.5-35b-a3b@llama.cpp.invalid>
kyleandornith-1.5-35b-a3b
7c40531891