stdout writeln (#2355)

diff --git a/codesign/bin/codesign.dart b/codesign/bin/codesign.dart
index 7197fde..965849d 100644
--- a/codesign/bin/codesign.dart
+++ b/codesign/bin/codesign.dart
@@ -8,6 +8,7 @@
 import 'package:codesign/codesign.dart';
 import 'package:file/file.dart';
 import 'package:file/local.dart';
+import 'package:logging/logging.dart';
 import 'package:platform/platform.dart';
 import 'package:process/process.dart';
 
@@ -63,6 +64,10 @@
 /// --output-zip-file-path=/b/output.zip
 /// ```
 Future<void> main(List<String> args) async {
+  Logger.root.onRecord.listen((LogRecord record) {
+    stdout.writeln(record.toString());
+  });
+
   final ArgParser parser = ArgParser();
   parser
     ..addFlag(