import type { TimelineGroup } from "../timeline/types.js";
/**
 * Settlement may compact history, but cannot remove prose beneath a reader.
 * Keep only progress that was already primary on the preceding commit; loading
 * settled history never expands it. An explicit work toggle or tip return ends
 * the protection. Keeping the original sibling keys also preserves selection.
 */
export declare function useReadingProgress(projected: TimelineGroup[], pinned: boolean, scroller: HTMLElement | null): {
    groups: TimelineGroup[];
    release: (id: string | null) => void;
};