Invoke SlashCommandExecuted event on failed type conversion (#314)

* added interaction specific interfaces

* fix build error

* implement change requests

* add autocomplete respond method to IAutocompleteInteraction

* fix sharded client current user

* fix generic typeconverter picking priority

* Revert "fix sharded client current user"

This reverts commit a9c15ffd6a.

* Revert "add autocomplete respond method to IAutocompleteInteraction"

This reverts commit f2fc50f1f1.

* fix command parsing for names with spaces

* add SlashCommandExecuted event invoke to failed type conversion

* update interactions sample app

* Revert "update interactions sample app"

This reverts commit 6ac8cd0da6.

src/Discord.Net.Interactions/Info/Commands/SlashCommandInfo.cs

@@ -81,7 +81,10 @@ namespace Discord.Interactions
                         var readResult = await typeConverter.ReadAsync(context, arg, services).ConfigureAwait(false);
 
                         if (!readResult.IsSuccess)
+                        {
+                            await InvokeModuleEvent(context, readResult).ConfigureAwait(false);
                             return readResult;
+                        }
 
                         args[i] = readResult.Value;
                     }