v4.5.2 - Fix hero parallax on iOS Safari

Bug Fixes

• Hero block: Fix background-attachment: fixed rendering incorrectly on iOS Safari, where the background image appeared zoomed/cropped because iOS sizes fixed backgrounds to the viewport instead of the element. The Hero block's background div now opts into the same media-query fallback already used by the Parallax block — parallax stays active on desktop, but switches to scroll on touch devices, small viewports, and prefers-reduced-motion. Samsung Internet and desktop browsers are unaffected.