chore: add simple example for TDD discovery

example/tdd_discovery.dart

@@ -0,0 +1,30 @@
+// Copyright 2024 Contributors to the Eclipse Foundation. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+//
+// SPDX-License-Identifier: BSD-3-Clause
+
+// ignore_for_file: avoid_print
+
+import "package:dart_wot/binding_http.dart";
+import "package:dart_wot/core.dart";
+
+Future<void> main() async {
+  final servient = Servient.create(
+    clientFactories: [
+      HttpClientFactory(),
+    ],
+  );
+  final wot = await servient.start();
+
+  final url = Uri.parse("http://plugfest.thingweb.io:8081");
+  print("Requesting TD from $url ...");
+  final thingDiscoveryProcess = await wot.exploreDirectory(url);
+
+  thingDiscoveryProcess.listen(
+    (thingDescription) => print(thingDescription.title),
+    onError: print,
+  );
+
+  await servient.shutdown();
+}