/** Write a value under a key, with an optional TTL in seconds. Returns expiresAt. */
export declare function stateWrite(cwd: string, key: string, value: unknown, ttlSeconds?: number): string | undefined;
/** Read a value. Returns { value: null } when missing; auto-deletes if expired. */
export declare function stateRead(cwd: string, key: string): {
    value: unknown;
    expired?: boolean;
};
export declare function stateDelete(cwd: string, key: string): void;
/** List live (non-expired) keys. */
export declare function stateList(cwd: string): string[];
/** Delete all expired entries; returns the count removed. */
export declare function stateCleanup(cwd: string): number;
export declare function stateStatus(cwd: string, key: string): {
    exists: boolean;
    mtime?: string;
    bytes?: number;
};