use *;
/// Reactive state for an element's visibility.
///
/// The handle carries the element the hook watches — a [`NodeRef`] the
/// caller attaches to its own markup — and the signals that report
/// whether the element is intersecting the viewport and how much of it
/// is visible.
///
/// This is the cheap way to defer the work of an off-screen element:
/// the signal only changes when the element actually crosses the
/// viewport, so a render closure that reads it stays quiet while the
/// element scrolls past.