import { type UsageAccount, type UsageHistoryScan } from "./ledger-schema.ts";
export declare function scanUsageHistory(root: string, from: number, to: number, windowStart: number): Promise<UsageHistoryScan>;
export declare function importUsageHistory(account: UsageAccount, history: UsageHistoryScan, at: number): void;
export declare function backfillUsage(key: string, sessionDir: string, signal?: AbortSignal): Promise<void> | undefined;