Resolve DI issue with initialized client; properly initialize command handling service.

samples/03_sharded_client/Program.cs

@@ -27,9 +27,8 @@ namespace _03_sharded_client
                 TotalShards = 2
             };
 
-            var services = ConfigureServices();
-
             _client = new DiscordShardedClient(config);
+            var services = ConfigureServices();
 
             // The Sharded Client does not have a Ready event.
             // The ShardReady event is used instead, allowing for individual
@@ -37,6 +36,8 @@ namespace _03_sharded_client
             _client.ShardReady += ReadyAsync;
             _client.Log += LogAsync;
 
+            await services.GetRequiredService<CommandHandlingService>().InitializeAsync();
+
             await _client.LoginAsync(TokenType.Bot, Environment.GetEnvironmentVariable("token"));
             await _client.StartAsync();