import type { ActivityPrincipal, ActivitySource, RecordActivityInput } from './types.js';
export declare function systemActivityActor(): ActivityPrincipal;
export declare function systemActivitySource(): ActivitySource;
export declare function previewText(value: string | undefined, maxLength?: number): string | undefined;
export declare function changedFieldsFromPatch(patch: Record<string, unknown>, ignoredKeys?: readonly string[]): string[];
export declare function emitActivity(input: RecordActivityInput): void;