Add debug logging for filename download issue

src/scripts/multiDownload.js

@@ -42,6 +42,9 @@ export default function (items) {
     // Support both old format (array of URLs) and new format (array of objects with url+filename)
     const isOldFormat = typeof items[0] === 'string';
 
+    console.log('multiDownload received items:', items);
+    console.log('isOldFormat:', isOldFormat);
+
     if (typeof document.createElement('a').download === 'undefined' || browser.iOS) {
         const urls = isOldFormat ? items : items.map(item => item.url || item);
         return fallback(urls);
@@ -52,6 +55,7 @@ export default function (items) {
     items.forEach(function (item) {
         const url = isOldFormat ? item : (item.url || item);
         const filename = isOldFormat ? '' : (item.filename || '');
+        console.log('Downloading:', { url, filename });
         setTimeout(download.bind(null, url, filename), 100 * ++delay);
     });
 }