feat(appointment): add expires_at and patient fields to Appointment

Add a 15-minute payment TTL (expires_at) plus patient_name/mobile/
national_code/gender/reason columns so a booking can hold a slot
temporarily and record a patient distinct from the paying user. New
markPendingWithTtl() sets the lock; transitioning out of pending clears
expires_at. All columns nullable (migration added).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

migrations/Version20260615142236.php

@@ -0,0 +1,31 @@
+<?php
+
+declare(strict_types=1);
+
+namespace DoctrineMigrations;
+
+use Doctrine\DBAL\Schema\Schema;
+use Doctrine\Migrations\AbstractMigration;
+
+/**
+ * Auto-generated Migration: Please modify to your needs!
+ */
+final class Version20260615142236 extends AbstractMigration
+{
+    public function getDescription(): string
+    {
+        return '';
+    }
+
+    public function up(Schema $schema): void
+    {
+        // this up() migration is auto-generated, please modify it to your needs
+        $this->addSql('ALTER TABLE appointments ADD expires_at INT DEFAULT NULL, ADD patient_name VARCHAR(150) DEFAULT NULL, ADD patient_mobile VARCHAR(20) DEFAULT NULL, ADD patient_national_code VARCHAR(20) DEFAULT NULL, ADD patient_gender VARCHAR(10) DEFAULT NULL, ADD patient_reason LONGTEXT DEFAULT NULL');
+    }
+
+    public function down(Schema $schema): void
+    {
+        // this down() migration is auto-generated, please modify it to your needs
+        $this->addSql('ALTER TABLE appointments DROP expires_at, DROP patient_name, DROP patient_mobile, DROP patient_national_code, DROP patient_gender, DROP patient_reason');
+    }
+}