A near-uniform drag collapses to the `scale` shorthand, but the finalize step
measured the element at the per-axis pair it computed rather than the single
value the commit writes. The element was measured at a scaleY the file never
gets, so the position correction came out tilted by the difference.
Adds a sweep over the shapes a composition produces — shrink, grow, first
resize, rotated, steeply rotated, non-uniform, near-zero, inline-sized, no
position write, animated position, and two drags in a row — each checking the
element renders on its drop point from the PERSISTED scale and position. The
geometry model is calibrated against real gesture traces: the same inputs
reproduce the rects the browser reported to three decimals.