- Rows that spill past the viewport edge used to render whole, ghosting over
the BUY title or onto the Confirm bar; now only elements fully inside the
window render (this Phaser build can't crop glyphs), and row plates draw
just their in-window slice for a clean cut.
- Clipped-out steppers are no longer tappable: hit-testing gates on element
containment, not just row visibility.
- Add a right-edge scrollbar (track + drag/jump thumb) that tracks scroll
position and hides when content fits the viewport.
- Extend shop-shot/dev tests to verify the clip invariant, dead-click
behavior, and scrollbar geometry; add a geckodriver screenshot helper.
