Two bugs in the scroll direction logic:
1. Vertical scroll with `pixels` ignores the `down` boolean because the
`??` operator bypasses the direction multiplier when pixels is provided.
Fix: move the direction multiplier outside the `??` so it applies to
both the pixels and numPages paths.
2. Horizontal scroll with `pixels` applies direction twice - once in
PageController.ts and again in actions.ts - causing a double negation
that reverses the intended direction. Fix: remove the redundant
direction logic from actions.ts since PageController already signs
the scroll amount.
Also removes the now-unused `down` and `right` parameters from the
scrollVertically() and scrollHorizontally() action functions.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
