feat: add package quantity normalization and AI suggestion handling in receipt import

flutter/lib/core/utils/pdf_opener_web.dart

@@ -1,3 +1,4 @@
+import 'dart:async';
 import 'dart:js_interop';
 import 'dart:typed_data';
 
@@ -14,6 +15,9 @@ Future<bool> openPdfBytes(Uint8List bytes) async {
     web.URL.revokeObjectURL(url);
     return false;
   }
-  web.URL.revokeObjectURL(url);
+  // Revoke later to avoid revoking before the new tab has loaded the blob.
+  Future<void>.delayed(const Duration(seconds: 30), () {
+    web.URL.revokeObjectURL(url);
+  });
   return true;
 }