/**
 * Research state persistence — file-backed JSON store.
 */
import type { ResearchState } from "../types/index.js";
export declare class ResearchStateStore {
    private filePath;
    constructor(repoPath: string, statePath: string);
    load(): Promise<ResearchState | null>;
    save(state: ResearchState): Promise<void>;
    initialize(tag: string, branch: string): Promise<ResearchState>;
    update(patch: Partial<ResearchState>): Promise<ResearchState>;
}