/**
 * Shared result types and field pickers for the durable remote task ledger's
 * pure conditional-transition functions (WFT-25) — split out of
 * `task-ledger-transitions.ts` / `task-ledger-transitions-cancellation.ts`
 * purely to keep both under this repository's file-size ceiling; there is no
 * behavioral reason to import this module directly instead of one of those.
 *
 * @module server/task-ledger-transition-helpers
 */
import type { WorkerExecutionIdentity } from '../worker/manifest/types.ts';
import type { RemoteTaskAttemptFields, RemoteTaskBase } from './task-ledger-types.ts';
export type TaskLedgerTransitionResult<T> = Readonly<{
    ok: true;
    nextRecord: T;
}> | Readonly<{
    ok: false;
    reason: string;
}>;
export type TaskLedgerPreconditionResult = Readonly<{
    ok: true;
}> | Readonly<{
    ok: false;
    reason: string;
}>;
export declare function pickBase(record: RemoteTaskBase): RemoteTaskBase;
export declare function pickAttemptFields(record: RemoteTaskAttemptFields): RemoteTaskAttemptFields;
export type LeaseHolderFields = Readonly<{
    attemptToken: string;
    workerSessionId: string;
    executionIdentity?: WorkerExecutionIdentity;
    attempt: number;
    leaseDeadline: number;
    firstQueuedAt: number;
    lastQueuedAt: number;
    startedAt: number;
    lastHeartbeatAt: number;
}>;
export declare function pickLeaseHolderFields(record: LeaseHolderFields): LeaseHolderFields;