refactor(booking): extract ServiceBookingCalculator from the controller

"Allowed duration of a service combination" lived inside
AppointmentController::serviceSlots(). Three upcoming callers need the same
computation (PATCH duration validation, service-aware reschedule, reserve
conversion); copying it would mean four variants with four different edge-case
behaviours.

The extraction is behaviour-preserving: BaseController::error() and
ExceptionSubscriber emit an identical envelope, so returning $this->error() was
replaced by throwing AppException with the same code/message/field.

Tenant ownership now goes through TenantOwnershipChecker::belongsToPair() (the
documented single point) instead of an inline section pair comparison. The repo
property is named itemRepo on purpose: TenantLookupInventoryTest only counts
recognised property names, so any other name would slip past the safety net.

The naive duration sum is kept deliberately — switching to solo/additional
minutes is task 04 and changes one line here.

Task: docs/new_feture/taskes/task-00-service-mode-completion/
Slot-mode contract: unchanged (--group=slot-mode-frozen green)

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

src/Appointment/Controller/AppointmentController.php

@@ -43,6 +43,7 @@ class AppointmentController extends BaseController
         private readonly \App\Appointment\Repository\AppointmentEventRepository $eventRepo,
         private readonly \App\Appointment\Security\AppointmentAccessChecker $accessChecker,
         private readonly \App\Appointment\Service\AppointmentInsuranceService $appointmentInsurance,
+        private readonly \App\Appointment\Service\ServiceBookingCalculator $serviceCalculator,
         private readonly \Psr\Log\LoggerInterface $logger,
     ) {}
 
@@ -207,46 +208,26 @@ class AppointmentController extends BaseController
             return $this->error(ErrorCodes::ERR_VALIDATION_001, 'انتخاب حداقل یک سرویس الزامی است', 422, 'service_item_uuids');
         }
 
-        // پیش از هر بررسی دیگری: سرویس باید مالِ همین محیط باشد. مسیر ثبت نوبت همین
-        // گارد را دارد و این مسیر نداشت، پس با uuid سرویسِ محیط دیگر می‌شد وجود،
-        // فعال‌بودن و مدتش را از پیام‌های خطا و اسلات‌های برگشتی استنتاج کرد.
-        if (($err = $this->assertServicesMatchContext($uuids, $doctor, $clinic)) !== null) {
-            return $err;
-        }
-
         // مدتِ override منشی (فقط برای همین محاسبه؛ پیش‌فرض سرویس تغییر نمی‌کند). durations[uuid]=minutes
-        $overrides = (array) $request->query->all('durations');
-
-        $totalMinutes = 0;
-        foreach ($uuids as $u) {
-            $item = $this->itemRepo->findByUuid($u);
-            if ($item === null) {
-                return $this->error(ErrorCodes::ERR_VALIDATION_002, 'سرویس یافت نشد', 422, 'service_item_uuids');
-            }
-            if (!$item->isBookable()) {
-                return $this->error(ErrorCodes::ERR_VALIDATION_001, 'این سرویس برای نوبت‌دهی فعال نیست', 422, 'service_item_uuids');
-            }
-            $duration = isset($overrides[$u]) && (int) $overrides[$u] > 0
-                ? (int) $overrides[$u]
-                : (int) ($item->getDurationMinutes() ?? 0);
-            if ($duration <= 0) {
-                return $this->error(ErrorCodes::ERR_VALIDATION_001, 'مدت سرویس تعریف نشده است', 422, 'service_item_uuids');
-            }
-            $totalMinutes += $duration;
-        }
-
-        $meta = $schedule ? $schedule->getMeta() : WeeklySchedule::DEFAULT_META;
+        // مالکیت محیط، وجود، فعال‌بودن و مدت — همه داخل calculate() و با همان ترتیب و
+        // همان کد/پیام/فیلدِ قبلی (AppException و $this->error() یک envelope می‌سازند).
+        $duration = $this->serviceCalculator->calculate(
+            $doctor,
+            $clinic,
+            $uuids,
+            (array) $request->query->all('durations'),
+        );
 
         return $this->success([
             'doctor_uuid'            => $doctorUuid,
             'date'                   => $date,
-            'total_duration_minutes' => $totalMinutes,
-            'buffer_minutes'         => (int) $meta['buffer_minutes'],
+            'total_duration_minutes' => $duration->totalMinutes,
+            'buffer_minutes'         => $duration->bufferMinutes,
             'clinic_uuid'            => $clinic?->getUuid(),
             'start_times'            => $this->slotCalculator->getServiceStartTimes(
                 $doctor,
                 $date,
-                $totalMinutes,
+                $duration->totalMinutes,
                 $clinic,
                 $this->isManagementContext($request, $doctor, $clinic),
             ),