feat(example): Improve the example code

examples_dart/lib/socket.dart

@@ -0,0 +1,22 @@
+import 'package:moxxmpp_socket_tcp/moxxmpp_socket_tcp.dart';
+
+/// A simple socket for examples that allows injection of SRV records (since
+/// we cannot use moxdns here).
+class ExampleTCPSocketWrapper extends TCPSocketWrapper {
+  ExampleTCPSocketWrapper(this.srvRecord);
+
+  /// A potential SRV record to inject for testing.
+  final MoxSrvRecord? srvRecord;
+
+  @override
+  bool onBadCertificate(dynamic certificate, String domain) {
+    return true;
+  }
+
+  @override
+  Future<List<MoxSrvRecord>> srvQuery(String domain, bool dnssec) async {
+    return [
+      if (srvRecord != null) srvRecord!,
+    ];
+  }
+}