feat: implement command bus with attribute-based handler resolution and add example command and handler (#27)

Reviewed-on: #27
Co-authored-by: Ron Rise <ron@siteworxpro.com>
Co-committed-by: Ron Rise <ron@siteworxpro.com>

src/Attributes/CommandBus/HandlesCommand.php

@@ -0,0 +1,22 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Siteworxpro\App\Attributes\CommandBus;
+
+use Attribute;
+
+/**
+ * Class HandlesCommand
+ * @package Siteworxpro\App\Attributes\CommandBus
+ */
+#[Attribute(Attribute::TARGET_CLASS)]
+readonly class HandlesCommand
+{
+    /**
+     * @param class-string $commandClass
+     */
+    public function __construct(public string $commandClass)
+    {
+    }
+}