docs: Clarify command samples (#1257)

* Clarify command samples by adding additional notes about each methods

* Add additional notes for the Program class

* Change wording on token read

* Change prefix sample to match referenced example

Co-Authored-By: Still34 <341464@gmail.com>

samples/02_commands_framework/Program.cs

@@ -37,10 +37,12 @@ namespace _02_commands_framework
                 client.Log += LogAsync;
                 services.GetRequiredService<CommandService>().Log += LogAsync;
 
-                // Tokens should be considered secret data, and never hard-coded.
+                // Tokens should be considered secret data and never hard-coded.
+                // We can read from the environment variable to avoid hardcoding.
                 await client.LoginAsync(TokenType.Bot, Environment.GetEnvironmentVariable("token"));
                 await client.StartAsync();
 
+                // Here we initialize the logic required to register our commands.
                 await services.GetRequiredService<CommandHandlingService>().InitializeAsync();
 
                 await Task.Delay(-1);