Remove the guest system entirely: no is_guest/device_id, no guest throttles, phone login is the only way in

accounts.0008 drops the columns and refuses to run while guest rows exist.
Docs describe the current state; tests that only proved guest behaviour are gone.

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

config/tests_audit_round2.py

@@ -30,7 +30,7 @@ def _client(user):
 class _Base(TestCase):
     def setUp(self):
         cache.clear()
-        self.user = User.objects.create(phone='09120008001', is_guest=False)
+        self.user = User.objects.create(phone='09120008001')
         self.client = _client(self.user)
         self.year = Plan.objects.create(title='سالانه', price=299000, duration_days=365)
 
@@ -57,18 +57,6 @@ class OfferNeverShortensSubscription(_Base):
         self.assertEqual(response.status_code, 200, response.content)
         self.assertEqual(Subscription.objects.get(user_id=self.user.id).expires_at, before)
 
-    @override_settings(DEV_MASTER_OTP='000000')
-    def test_guest_who_paid_keeps_the_year_after_registering(self):
-        Offer.objects.create(name='هفته رایگان', kind='trial', duration_days=7,
-                             auto_assign_on_signup=True)
-        guest = User.objects.create(device_id='audit-2-device', is_guest=True)
-        guest_client = _client(guest)
-        self.pay(self.buy(guest_client), ref='R2')
-        response = guest_client.post('/api/auth/login', {'phone': '09125550001', 'otp': '000000'},
-                                     format='json')
-        self.assertEqual(response.status_code, 200, response.content)
-        days = (Subscription.objects.get(user_id=guest.id).expires_at - timezone.now()).days
-        self.assertGreater(days, 360)
 
     def test_trial_still_works_for_a_user_without_subscription(self):
         Offer.objects.create(name='هفته رایگان', kind='trial', duration_days=7, code='WEEK')