Adds header support for substack articles#7

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mhstoller wants to merge 2 commits intoXatpy:mainfrom

mhstoller:5009-fix-html-parsing

Commits on Feb 20, 2026

Preserve article headings in EPUB extraction and add helper tests
mhstoller
committed
Clarify Substack-like structured fallback in extraction comments
mhstoller
committed