fix: load the pdf.js worker with the Map upsert polyfill

src/js/utils/setup-pdf-worker.ts

@@ -0,0 +1,4 @@
+import * as pdfjsLib from 'pdfjs-dist';
+import pdfWorkerUrl from '../pdf.worker?worker&url';
+
+pdfjsLib.GlobalWorkerOptions.workerSrc = pdfWorkerUrl;