Migrate backend to Porto architecture and fix minor bugs

- Fully transitioned the backend to the Porto architectural pattern
- Improved code organization and maintainability
- Fixed minor bugs and inconsistencies

app/Ship/Abstracts/Notifications/Notification.php

@@ -0,0 +1,11 @@
+<?php
+
+namespace App\Ship\Abstracts\Notifications;
+
+use Illuminate\Notifications\Notification as LaravelNotification;
+use Illuminate\Bus\Queueable;
+
+abstract class Notification extends LaravelNotification
+{
+    use Queueable;
+}