Use top-level statements in demo

CliFx.Demo/Program.cs

@@ -1,35 +1,25 @@
-using System;
-using System.Threading.Tasks;
+using CliFx;
 using CliFx.Demo.Commands;
 using CliFx.Demo.Domain;
 using Microsoft.Extensions.DependencyInjection;
 
-namespace CliFx.Demo;
+// We use Microsoft.Extensions.DependencyInjection for injecting dependencies in commands
+var services = new ServiceCollection();
 
-public static class Program
-{
-    private static IServiceProvider GetServiceProvider()
-    {
-        // We use Microsoft.Extensions.DependencyInjection for injecting dependencies in commands
-        var services = new ServiceCollection();
+// Register services
+services.AddSingleton<LibraryProvider>();
 
-        // Register services
-        services.AddSingleton<LibraryProvider>();
+// Register commands
+services.AddTransient<BookCommand>();
+services.AddTransient<BookAddCommand>();
+services.AddTransient<BookRemoveCommand>();
+services.AddTransient<BookListCommand>();
 
-        // Register commands
-        services.AddTransient<BookCommand>();
-        services.AddTransient<BookAddCommand>();
-        services.AddTransient<BookRemoveCommand>();
-        services.AddTransient<BookListCommand>();
+var serviceProvider = services.BuildServiceProvider();
 
-        return services.BuildServiceProvider();
-    }
-
-    public static async Task<int> Main() =>
-        await new CliApplicationBuilder()
+return await new CliApplicationBuilder()
     .SetDescription("Demo application showcasing CliFx features.")
     .AddCommandsFromThisAssembly()
-            .UseTypeActivator(GetServiceProvider().GetRequiredService)
+    .UseTypeActivator(serviceProvider.GetRequiredService)
     .Build()
     .RunAsync();
-}