feat(appointment): treat expired pending bookings as free in isSlotTaken

A slot is taken only if confirmed, or pending with a still-valid lock
(expires_at null or in the future). An expired pending booking no longer
blocks the slot even before the cron flips it to expired.

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

src/Appointment/Repository/AppointmentRepository.php

@@ -27,11 +27,15 @@ class AppointmentRepository extends ServiceEntityRepository
         $qb = $this->createQueryBuilder('a')
             ->select('COUNT(a.id)')
             ->where('a.doctor = :doctor')
-            ->andWhere('a.status IN (:activeStatuses)')
             ->andWhere('a.slotStart < :slotEnd')
             ->andWhere('a.slotEnd > :slotStart')
+            ->andWhere(
+                'a.status = :confirmed OR (a.status = :pending AND (a.expiresAt IS NULL OR a.expiresAt > :now))'
+            )
             ->setParameter('doctor', $doctor)
-            ->setParameter('activeStatuses', [Appointment::STATUS_PENDING, Appointment::STATUS_CONFIRMED])
+            ->setParameter('confirmed', Appointment::STATUS_CONFIRMED)
+            ->setParameter('pending', Appointment::STATUS_PENDING)
+            ->setParameter('now', time())
             ->setParameter('slotStart', $slotStart)
             ->setParameter('slotEnd', $slotEnd);