/**
 * A hook that tracks whether the current tab/page is visible to the user.
 * Returns true when the page is visible, false when hidden.
 * Defaults to true during SSR for optimistic rendering.
 *
 * @returns boolean indicating if the page is visible
 *
 * @example
 * const isVisible = usePageVisibility();
 * if (isVisible) {
 *   // Page is active, run animations or fetch data
 * }
 */
export declare function usePageVisibility(): boolean;