add controller to see group's messages

src/Application/Actions/Message/GroupMessagesListAction.php

+<?php
+declare(strict_types=1);
+
+namespace App\Application\Actions\Message;
+use App\Domain\Group\Group ;
+
+use Psr\Http\Message\ResponseInterface as Response;
+
+class GroupMessagesListAction extends MessageAction
+{
+    /**
+     * {@inheritdoc}
+     */
+    protected function action(): Response
+    {
+        $groupId = (int) $this->resolveArg('id');
+        $group = $this->groupRepository->find($groupId);
+ 
+        if (!isset($_SESSION['userId']) || !$group->hasUser($_SESSION['userId'])){
+
+            return $this->response
+            ->withHeader('Location', '/groups/')
+            ->withStatus(302);
+        }
+
+        $transmitter_id = $_SESSION['userId'];
+
+        $messages = $this->messageRepository->findBy(array('receiver' => $groupId), array('date' => 'ASC'));
+
+        $this->logger->info("Messages list was viewed.");
+
+        return $this->twig->render($this->response, "/message/messenger.twig", ["messages" => $messages, "group" => $group, 'session' => $_SESSION]);
+    }
+}