Implements Task 20: clickable Fig./Figure N mentions in paragraph text open a
FigurePopover with the figure image, caption, and five-mode streaming annotator,
reusing CitePopover chrome and NoteBody extracted from MarginNote. Adds the 7th
pipeline stage row (vii · Tipping in the plates · pymupdf), extends session
round-trip with figures/litByFig, and generalises generate() to resolve both
paragraph and figure targets.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
