/**
 * Schema-fence document. Vault-level generation counter + drain
 * state, stored at `_meta/schema-fence` using the plaintext-envelope
 * pattern of `_meta/policy` (no PII — a counter + a state enum).
 */
import type { NoydbStore } from '../../kernel/types.js';
export type FenceState = 'normal' | 'draining' | 'migrating' | 'complete';
export interface FenceDoc {
    readonly currentSchemaVersion: number;
    readonly fenceState: FenceState;
}
export declare const FENCE_RECORD_ID = "schema-fence";
export declare const DEFAULT_FENCE: FenceDoc;
export declare function loadFence(store: NoydbStore, vault: string): Promise<FenceDoc>;
export declare function saveFence(store: NoydbStore, vault: string, fence: FenceDoc): Promise<void>;