Non-PDF fixed-layout EPUBs visually scale the iframe via CSS transform
while keeping native dimensions inside, so getClientRects() returns
unscaled positions. The SVG overlayer was sized in CSS pixels with no
viewBox, leaving annotations and TTS highlights drawn at scale-1
displacement from the actual text.
Bumps foliate-js to set a matching viewBox on the overlayer SVG, and
adds a regression test covering spread/scroll/PDF/empty frames.
Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Huang Xin