/** Pure session-fork boundary policy shared by the TUI command and tests. */
import type { SessionEvent } from '@deepseek-ai/dsh-session';
export interface ForkSeed {
    readonly boundarySeq: number;
    readonly events: readonly SessionEvent[];
}
/** Select a completed turn and trailing between-turn metadata. */
export declare function selectForkSeed(events: readonly SessionEvent[], atSeq?: number): ForkSeed;