feat(core): improve in-memory validation, FatturaPA detection coverage, and published type compatibility

test/strict-consumer/index.ts

@@ -0,0 +1,16 @@
+import { EInvoice } from '../../dist_ts/index.js';
+import * as plugins from '../../dist_ts/plugins.js';
+
+const invoice = new EInvoice();
+invoice.pdf = undefined;
+invoice.pdfAttachments = undefined;
+
+const parser = new plugins.DOMParser();
+const parserFromNamespace = new plugins.xmldom.DOMParser();
+
+void invoice;
+void parser;
+void parserFromNamespace;
+void plugins.pako.inflate;
+void plugins.SaxonJS.compile;
+void plugins.SaxonJS.transform;