add email signup flow

backend/app/Email/EmailConfirmationToken/CreateEmailConfirmationTokenDto.php

@@ -0,0 +1,15 @@
+<?php
+
+namespace App\Email\EmailConfirmationToken;
+
+use App\User\User;
+use DateTimeImmutable;
+
+final readonly class CreateEmailConfirmationTokenDto
+{
+    public function __construct(
+        public User $user,
+        public DateTimeImmutable $availableTo,
+        public string $token,
+    ) {}
+}