/**
 * Returns `false` during SSR and the first render, `true` after hydration.
 * Use to guard browser-only code and prevent hydration mismatches.
 *
 * @returns {boolean} Whether the component has mounted
 *
 * @example
 * const mounted = useMounted();
 * // Only render browser-dependent UI after mount
 * return mounted ? <LocalTime /> : <span>--:--</span>;
 */
export declare function useMounted(): boolean;