feat: groups price calculator admin crud, booking/offer flow and api

src/Exception/AccommodationSessionNotFoundException.php

@@ -0,0 +1,15 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Exception;
+
+use Symfony\Component\HttpKernel\Exception\HttpException;
+
+class AccommodationSessionNotFoundException extends HttpException
+{
+    public function __construct(?\Throwable $previous = null)
+    {
+        parent::__construct(404, 'No valid accommodation inquiry session found.', $previous);
+    }
+}