feat(events): harden registration checkout lifecycle

config/services/celery.py

@@ -38,6 +38,21 @@ app.conf.beat_schedule = {
         'schedule': crontab(hour=2, minute=0),
         'description': 'Runs daily at 02:00 UTC to cleanup notification retention.',
     },
+    'sweep-stale-payment-verifications': {
+        'task': 'apps.payments.sweep_stale_payment_verifications',
+        'schedule': crontab(minute='*/5'),
+        'description': 'Recovers old unresolved payment attempts with bounded gateway verification.',
+    },
+    'expire-stale-registration-checkouts': {
+        'task': 'apps.events.expire_stale_registration_checkouts',
+        'schedule': crontab(minute='*'),
+        'description': 'Releases seats from paid checkouts after their 15-minute window.',
+    },
+    'sweep-pending-refunds': {
+        'task': 'apps.payments.sweep_pending_refunds',
+        'schedule': crontab(minute='*/5'),
+        'description': 'Recovers pending transaction reversals and exposes exhausted attempts for admin review.',
+    },
 }
 
 CELERY_TASK_SOFT_TIME_LIMIT = 20

config/services/zarinpal.py

@@ -6,5 +6,6 @@ ZARINPAL_USE_SANDBOX = config('ZARINPAL_USE_SANDBOX', default=False, cast=bool)
 ZARINPAL_API_BASE = "https://sandbox.zarinpal.com" if ZARINPAL_USE_SANDBOX else "https://payment.zarinpal.com"
 ZARINPAL_REQUEST_URL = f"{ZARINPAL_API_BASE}/pg/v4/payment/request.json"
 ZARINPAL_VERIFY_URL  = f"{ZARINPAL_API_BASE}/pg/v4/payment/verify.json"
+ZARINPAL_REVERSE_URL = f"{ZARINPAL_API_BASE}/pg/v4/payment/reverse.json"
 ZARINPAL_STARTPAY    = f"{ZARINPAL_API_BASE}/pg/StartPay/"
 ZARINPAL_CALLBACK_URL = config('ZARINPAL_CALLBACK_URL', default='http://localhost:8000/api/payments/callback')