Previously, clip-path was applied only during painting in
StackingContext::paint(), which meant hit testing did not respect
clip-path boundaries. Clicks outside the visible clipped region but
inside the element's bounding box would incorrectly register as hits.
By moving clip-path into AccumulatedVisualContext, it becomes part of
the same system that handles transforms, clips, and scroll offsets for
both painting and hit testing, ensuring consistent behavior.
This test demonstrates the current broken behavior where hit testing
does not respect clip-path boundaries. Clicking outside the clipped
circle (but inside the element's bounding box) incorrectly registers
as a hit on the element.
