export declare class ValidationError extends Error { readonly code: string; readonly details?: Record | null; constructor(message: string, details?: Record); toJSON(): { message: string; name: string; code: string; details: Record | null | undefined; }; } export declare class StateError extends Error { readonly code: string; readonly sessionId?: string; constructor(message: string, sessionId?: string); toJSON(): { message: string; name: string; code: string; sessionId: string | undefined; }; } export declare class SecurityError extends Error { readonly code: string; readonly severity: 'low' | 'medium' | 'high' | 'critical'; constructor(message: string, severity?: 'low' | 'medium' | 'high' | 'critical'); toJSON(): { message: string; name: string; code: string; severity: "low" | "medium" | "high" | "critical"; }; } export declare class ProcessingError extends Error { readonly code: string; readonly context?: Record | null; constructor(message: string, context?: Record); toJSON(): { message: string; name: string; code: string; context: Record | null | undefined; }; } export interface ErrorResponse { code: string; message: string; details?: Record | null; timestamp: string; requestId?: string; }