feat: add registration page with form validation

src/Controller/RegistrationController.php

@@ -0,0 +1,47 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Controller;
+
+use App\Entity\User;
+use App\Form\RegistrationType;
+use Doctrine\ORM\EntityManagerInterface;
+use Symfony\Bundle\FrameworkBundle\Controller\AbstractController;
+use Symfony\Component\HttpFoundation\Request;
+use Symfony\Component\HttpFoundation\Response;
+use Symfony\Component\PasswordHasher\Hasher\UserPasswordHasherInterface;
+use Symfony\Component\Routing\Attribute\Route;
+
+class RegistrationController extends AbstractController
+{
+    #[Route('/register', name: 'app_register')]
+    public function register(
+        Request $request,
+        UserPasswordHasherInterface $passwordHasher,
+        EntityManagerInterface $entityManager,
+    ): Response {
+        if ($this->getUser()) {
+            return $this->redirectToRoute('app_homepage');
+        }
+
+        $user = new User();
+        $form = $this->createForm(RegistrationType::class, $user);
+        $form->handleRequest($request);
+
+        if ($form->isSubmitted() && $form->isValid()) {
+            $user->setPassword(
+                $passwordHasher->hashPassword($user, $form->get('plainPassword')->getData())
+            );
+
+            $entityManager->persist($user);
+            $entityManager->flush();
+
+            return $this->redirectToRoute('app_login');
+        }
+
+        return $this->render('security/register.html.twig', [
+            'registrationForm' => $form,
+        ]);
+    }
+}