Four new extraction research documents covering page label/PageLabels
number tree and outline/bookmark tree extraction, government form PDF
patterns (IRS, USCIS, court filings, classification markings), book and
publishing PDF structure (running heads, footnotes, index extraction),
and PDF stream filter pipeline (FlateDecode/LZW predictors, JBIG2 global
segments, CCITTFax, JPX, error boundaries).
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
