Secrets config for CI/CD

tool/secrets.dart

@@ -0,0 +1,11 @@
+import 'dart:convert';
+import 'dart:io';
+
+Future<void> main() async {
+  final config = {
+    'syncfusion_license_key': Platform.environment['SYNCFUSION_LICENSE_KEY'],
+  };
+
+  final filename = 'lib/.secrets.dart';
+  File(filename).writeAsString('final secrets = ${json.encode(config)};');
+}