init id before super

lib/async_vid/shell/reader.dart

@@ -8,15 +8,14 @@ import '../reader.dart';
 
 class AsyncShellVidDataReader extends AsyncVidDataReaderBase {
   final int minChunkSize;
-  late final String id;
+  late final String id =
+      DateTime.now().format('MMddHHmmssSSS') + hashCode.toString();
 
   AsyncShellVidDataReader(
     String url, {
     DownloadCallback? downloadCallback,
     this.minChunkSize = 65536,
-  }) : super(url, downloadCallback: downloadCallback) {
-    id = DateTime.now().format('MMddHHmmssfff') + hashCode.toString();
-  }
+  }) : super(url, downloadCallback: downloadCallback);
 
   @override
   void close() {