/**
 * Observes an element for inline-size (width) changes and calls `onWidthChange`
 * when the width changes. Height-only changes are ignored to prevent infinite
 * loops when the callback adjusts the element's height.
 *
 * Unlike useResizeObserver from the component-toolkit package, it does not cause
 * re-renders when the width changes.
 *
 * @param elementRef - A ref object pointing to the element to observe.
 * @param onWidthChange - Callback fired when the element's width changes.
 */
export declare function useWidthChange(elementRef: React.RefObject<HTMLElement>, onWidthChange: () => void): void;