feat(secretary): implement multi-doctor assignment for clinic secretaries

- Added functionality to assign a single secretary to multiple doctors within a clinic, allowing for scoped access to appointments.
- Introduced `SecretaryService` to handle the logic for assigning and syncing doctors for a secretary.
- Updated `SecretaryController` to support multi-doctor assignment via new endpoints and modified existing ones.
- Enhanced `DoctorSecretary` entity to include secretary UUID in its serialized output.
- Implemented repository methods to facilitate the retrieval and management of doctor-secretary relationships.
- Adjusted appointment filtering in `MyAppointmentsController` to ensure secretaries only see appointments for assigned doctors.
- Created tests to validate the new multi-doctor assignment functionality and appointment access restrictions.
- Updated frontend components to support multi-select for doctors in the secretary management UI.

src/Secretary/Repository/DoctorSecretaryRepository.php

@@ -88,12 +88,25 @@ class DoctorSecretaryRepository extends ServiceEntityRepository
             ->getOneOrNullResult();
     }
 
+    /** رابطه فعالِ owner=clinic برای یک (منشی، کلینیک، پزشک) مشخص */
+    public function findActiveClinicRow(User $user, Clinic $clinic, Doctor $doctor): ?DoctorSecretary
+    {
+        return $this->findOneBy([
+            'secretary' => $user,
+            'clinic'    => $clinic,
+            'doctor'    => $doctor,
+            'ownerType' => DoctorSecretary::OWNER_CLINIC,
+            'active'    => true,
+        ]);
+    }
+
     /** همه دکترهای کلینیک که این منشی به آن‌ها متصل است */
     public function findDoctorsBySecretaryInClinic(User $user, Clinic $clinic): array
     {
-        return $this->createQueryBuilder('s')
+        return $this->getEntityManager()->createQueryBuilder()
             ->select('d')
-            ->join('s.doctor', 'd')
+            ->from(Doctor::class, 'd')
+            ->join(DoctorSecretary::class, 's', 'WITH', 's.doctor = d')
             ->where('s.secretary = :user')
             ->andWhere('s.clinic = :clinic')
             ->andWhere('s.ownerType = :type')
@@ -122,6 +135,22 @@ class DoctorSecretaryRepository extends ServiceEntityRepository
         return $clinic->getDoctors()->contains($doctor);
     }
 
+    /** روابط owner_type='clinic' یک منشی مشخص در یک کلینیک (فعال و غیرفعال، برای sync) */
+    public function findByClinicAndSecretary(Clinic $clinic, User $secretary): array
+    {
+        return $this->createQueryBuilder('s')
+            ->addSelect('doc')
+            ->join('s.doctor', 'doc')
+            ->where('s.clinic = :clinic')
+            ->andWhere('s.secretary = :secretary')
+            ->andWhere('s.ownerType = :type')
+            ->setParameter('clinic', $clinic)
+            ->setParameter('secretary', $secretary)
+            ->setParameter('type', DoctorSecretary::OWNER_CLINIC)
+            ->getQuery()
+            ->getResult();
+    }
+
     /** همه منشی ها کلینیک (owner_type='clinic') */
     public function findByClinic(Clinic $clinic): array
     {