add email signup flow

backend/app/User/EloquentUserRepository.php

@@ -3,6 +3,7 @@
 namespace App\User;
 
 use App\Shared\ValueObject\EmailAddress;
+use DomainException;
 
 class EloquentUserRepository implements UserRepository
 {
@@ -38,6 +39,22 @@ class EloquentUserRepository implements UserRepository
         return $this->toDomain($model);
     }
 
+    public function update(User $user): User
+    {
+        $model = UserModel::find($user->getId());
+        if ($model === null) {
+            throw new DomainException(
+                "User with id {$user->getId()} not found",
+            );
+        }
+
+        $model->email = $user->getEmail()->value();
+        $model->passwordHash = $user->getPasswordHash();
+        $model->save();
+
+        return $this->toDomain($model);
+    }
+
     private function toDomain(UserModel $model): User
     {
         return new User(