Ui/Anchor

/**
 * Positions a floating element relative to its button using Floating UI, then
 *  returns a cleanup function. Designed to be called inside an `OnMount`
 *  action: the consumer wraps the call in `Effect.sync` and stashes the
 *  returned cleanup in the `Mount` result. When `interceptTab` is true
 *  (default), Tab key in portal mode refocuses the button. Set to false for
 *  components like Popover where Tab should navigate naturally within the
 *  panel. When `focusAfterPosition` is true, the element is focused after the
 *  first position computation clears visibility, deferred via
 *  requestAnimationFrame so the element is painted before focus fires.
 *  `focusSelector` optionally targets a descendant (e.g. a calendar grid
 *  inside a popover panel) instead of the panel itself.
 *  The side the element currently sits on is written to `data-placement`, so
 *  CSS can react to it. When `isPlacementLocked` is true, the element keeps the
 *  side that the first positioning picks, `flip` is removed from every later
 *  update, and `data-placement` holds that locked side. Otherwise the attribute
 *  tracks the side each update resolves to, including the ones `flip` moves.
 */
(config: {
  anchor: Anchor.AnchorConfig
  buttonId: string
  focusAfterPosition: boolean
  focusSelector: string
  interceptTab: boolean
}): (element: Element) => () => void

/**
 * Relocates an element into the shared `foldkit-portal-root` div within its
 *  containing root: the shadow root when mounted inside one, otherwise
 *  `document.body`. Escapes any ancestor stacking context while keeping the
 *  element under that root's scoped styles. Returns a cleanup function that
 *  removes the element from the portal root. Designed to be called from inside
 *  an `OnMount` action: the consumer wraps the call in `Effect.sync` and
 *  stashes the returned cleanup in the `Mount` result.
 */
(element: Element): () => void