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/Middleware/LimitPost.php

@@ -0,0 +1,28 @@
+<?php
+
+namespace App\Ship\Middleware;
+
+use Closure;
+use Illuminate\Http\Request;
+use Symfony\Component\HttpFoundation\Response;
+use Symfony\Component\HttpKernel\Exception\HttpException;
+
+class LimitPost
+{
+    /**
+     * Handle an incoming request.
+     *
+     * @param  \Closure(\Illuminate\Http\Request): (\Symfony\Component\HttpFoundation\Response)  $next
+     */
+    public function handle(Request $request, Closure $next): Response
+    {
+        if (auth()->user()->receivedInvitation === null) {
+            return $next($request);
+        }
+        if (auth()->user()->receivedInvitation->post_limit > 0) {
+            return $next($request);
+        } else {
+            throw new HttpException(403, 'Лимит постов исчерпан');
+        }
+    }
+}