BREAKING CHANGE(XInvoice): Refactor XInvoice API for XML handling and PDF export by replacing deprecated methods (addXmlString and getParsedXmlData) with fromXml and loadXml, and by introducing a new ExportFormat type for type-safe export. Update tests accordingly.

ts/index.ts

@@ -26,6 +26,7 @@ export type {
   ValidationResult,
   ValidationLevel,
   InvoiceFormat,
+  ExportFormat,
   XInvoiceOptions,
   IValidator
 } from './interfaces.js';