Add dotnet activities for train interface.

enterprise/Program.cs

@@ -0,0 +1,52 @@
+using Microsoft.Extensions.DependencyInjection;
+using Temporalio.Client;
+using Temporalio.Worker;
+using TrainSearchWorker.Activities;
+
+var services = new ServiceCollection();
+
+// Add HTTP client
+services.AddHttpClient("TrainApi", client =>
+{
+    client.BaseAddress = new Uri("http://localhost:8080/");
+    client.DefaultRequestHeaders.Add("Accept", "application/json");
+});
+
+// Add activities
+services.AddScoped<TrainActivities>();
+
+var serviceProvider = services.BuildServiceProvider();
+
+// Create client
+var client = await TemporalClient.ConnectAsync(new()
+{
+    TargetHost = "localhost:7233",
+});
+
+// Create worker options
+var options = new TemporalWorkerOptions("agent-task-queue-legacy");
+
+// Register activities
+var activities = serviceProvider.GetRequiredService<TrainActivities>();
+options.AddActivity(activities.SearchTrains);
+options.AddActivity(activities.BookTrains);
+
+// Create and run worker
+var worker = new TemporalWorker(client, options);
+
+Console.WriteLine("Starting worker...");
+using var tokenSource = new CancellationTokenSource();
+Console.CancelKeyPress += (_, eventArgs) =>
+{
+    eventArgs.Cancel = true;
+    tokenSource.Cancel();
+};
+
+try 
+{
+    await worker.ExecuteAsync(tokenSource.Token);
+}
+catch (OperationCanceledException)
+{
+    Console.WriteLine("Worker shutting down...");
+}