Add production Greenlight credentials example

snippets/dart_snippets/lib/production.dart

@@ -0,0 +1,21 @@
+import 'dart:typed_data';
+
+import 'package:breez_sdk/breez_sdk.dart';
+import 'package:breez_sdk/bridge_generated.dart';
+
+NodeConfig productionNodeConfig() {
+  // ANCHOR: moving-to-production
+  // Read your Greenlight credentials from secure storage
+  Uint8List deviceKey = Uint8List();
+  Uint8List deviceCert = Uint8List();
+  GreenlightCredentials greenlightCredentials = GreenlightCredentials(deviceKey, deviceCert);
+
+  NodeConfig nodeConfig = NodeConfig.greenlight(
+    config: GreenlightNodeConfig(
+      partnerCredentials: greenlightCredentials,
+      inviteCode: null,
+    ),
+  );
+  // ANCHOR_END: moving-to-production
+  return nodeConfig
+}