/**
 * 24h mode persistence — atomic JSON snapshot under
 * `.peaks/_runtime/<sessionId>/24h-state.json`.
 *
 * the caller passes one (the CLI resolves it from `.peaks/_runtime/session.json`).
 * Writes use the temp-file + rename pattern so a crash mid-write never
 * leaves a half-written state file (atomic on POSIX, near-atomic on
 * Windows — same approach used by `session-checkpoint-service.ts`).
 */
import { type State24hSnapshot } from './state.js';
export declare function emptySnapshot(now?: Date): State24hSnapshot;
export declare function read24hState(projectRoot: string, sessionId: string): State24hSnapshot;
/**
 * Atomic write: temp file in the same directory, then rename. The
 * rename is a single syscall on POSIX and a single MoveFile on
 * Windows — a crash in between leaves the previous valid snapshot
 * intact. `fsync` on the temp file is omitted (we accept the
 * same weaker contract that `session-checkpoint-service.ts` uses)
 * because the state is reconstructible from the B3 attempt log.
 */
export declare function write24hState(projectRoot: string, sessionId: string, snapshot: State24hSnapshot): {
    path: string;
};
export declare const STATE_STORE_CONSTANTS: {
    readonly STATE_FILENAME: "24h-state.json";
};