feat: MailJet list handling with DOI, webhook receiver and API endpoint

addresses #869cut134

migrations/Version20260423120000.php

@@ -0,0 +1,26 @@
+<?php
+
+declare(strict_types=1);
+
+namespace DoctrineMigrations;
+
+use Doctrine\DBAL\Schema\Schema;
+use Doctrine\Migrations\AbstractMigration;
+
+final class Version20260423120000 extends AbstractMigration
+{
+    public function getDescription(): string
+    {
+        return 'Store optional first and last names on newsletter opt-in confirmations';
+    }
+
+    public function up(Schema $schema): void
+    {
+        $this->addSql("ALTER TABLE newsletter_opt_in_confirmation ADD first_name VARCHAR(255) DEFAULT NULL, ADD last_name VARCHAR(255) DEFAULT NULL");
+    }
+
+    public function down(Schema $schema): void
+    {
+        $this->addSql('ALTER TABLE newsletter_opt_in_confirmation DROP first_name, DROP last_name');
+    }
+}