Refactor engine structure: remove legacy files and introduce new architecture

- Deleted legacy model.php, proxy.php, registry.php, and router.php files.
- Added new action.php, controller.php, event.php, loader.php, model.php, proxy.php, registry.php, and router.php files to implement a more modular and maintainable structure.
- Introduced an event-driven architecture for better extensibility.
- Updated loader functionality to handle controllers, models, views, libraries, helpers, and configurations.
- Ensured compatibility with OpenCart standards and improved error handling.
- Created a new DDEV configuration file for streamlined development environment setup.

public/system/config/engine/proxy.php

@@ -0,0 +1,54 @@
+<?php
+/**
+ * @package		OpenCart
+ * @author		Daniel Kerr
+ * @copyright	Copyright (c) 2005 - 2017, OpenCart, Ltd. (https://www.opencart.com/)
+ * @license		https://opensource.org/licenses/GPL-3.0
+ * @link		https://www.opencart.com
+*/
+
+/**
+* Proxy class
+*/
+class Proxy {
+    /**
+     * 
+     *
+     * @param	string	$key
+     */	
+	public function __get($key) {
+		return $this->{$key};
+	}	
+
+    /**
+     * 
+     *
+     * @param	string	$key
+	 * @param	string	$value
+     */	
+	public function __set($key, $value) {
+		 $this->{$key} = $value;
+	}
+	
+	public function __call($key, $args) {
+		$arg_data = array();
+		
+		$args = func_get_args();
+		
+		foreach ($args as $arg) {
+			if ($arg instanceof Ref) {
+				$arg_data[] =& $arg->getRef();
+			} else {
+				$arg_data[] =& $arg;
+			}
+		}
+		
+		if (isset($this->{$key})) {		
+			return call_user_func_array($this->{$key}, $arg_data);	
+		} else {
+			$trace = debug_backtrace();
+			
+			exit('<b>Notice</b>:  Undefined property: Proxy::' . $key . ' in <b>' . $trace[1]['file'] . '</b> on line <b>' . $trace[1]['line'] . '</b>');
+		}
+	}
+}