/**
 * Sync SHA-256 hex digest for realtime envelope checksum verification (browser + Node).
 * Shared by kiosk SSE validator and customer shop SSE unwrap (fail-closed contract).
 */
export declare function sha256Hex(value: string): string;
export interface RealtimeEnvelope {
    readonly eventId: string;
    readonly eventVersion: number;
    readonly eventType: string;
    readonly tenantId: number;
    readonly aggregateId: string;
    readonly sequence: number;
    readonly emittedAt: string;
    readonly payload: Record<string, unknown>;
    readonly checksum: string;
}
export declare const SUPPORTED_REALTIME_EVENT_VERSION = 1;
export declare const REALTIME_SSE_VALIDATION_CODES: {
    readonly UNSUPPORTED_VERSION: "STREAM_UNSUPPORTED_VERSION";
    readonly CHECKSUM_MISMATCH: "STREAM_CHECKSUM_MISMATCH";
};
export declare function isRealtimeEnvelope(parsed: unknown): parsed is RealtimeEnvelope;
export declare function verifyEnvelopeChecksum(envelope: RealtimeEnvelope): boolean;
export declare function isSupportedRealtimeEnvelopeVersion(envelope: RealtimeEnvelope): boolean;
//# sourceMappingURL=realtimeEnvelope.d.ts.map