Bazaar: subscriptions (10343/10344), dynamic price (discount codes on Bazaar), auto-renewal sync

- Purchase with paymentMethod=bazaar now works for subscription plans with a bazaar_sku (not only packs);
  response carries bazaarProductType. Migration subscription.0014 puts 10343/10344 on the 90/180-day plans.
- Verify asks Bazaar for the right product type (from the order) and stores validUntil (payment.0012).
- POST /api/payment/bazaar/orders/{id}/start: SKU, type, and an HS256 dynamic-price JWT when a discount
  code lowered the price (BAZAAR_DYNAMIC_PRICE_KEY); discount on Bazaar orders allowed only with that key
  and only before start.
- Auto-renewal: sync_bazaar_renewals re-asks Bazaar when the paid period is near its end (status page and
  the paywall via has_subscription_access); each new period becomes a paid order.
- Default BAZAAR_PACKAGE_NAME = com.tadrisino.math.app; health shows bazaarDynamicPrice.
979 tests green. No real Bazaar purchase or renewal tested.

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

payment/tests_bazaar_oauth.py

@@ -195,7 +195,7 @@ class BazaarValidateAgainstDocsTests(TestCase):
         self.assertTrue(bazaar.verify_purchase(product_sku='sub', purchase_token='t', is_subscription=True).is_valid)
         self.assertEqual(
             mock_get.call_args.args[0],
-            'https://pardakht.cafebazaar.ir/devapi/v2/api/applications/ir.example.app/subscriptions/sub/purchases/t',
+            'https://pardakht.cafebazaar.ir/devapi/v2/api/applications/ir.example.app/subscriptions/sub/purchases/t/',
         )
         self._resp(mock_get, 200, {'validUntilTimestampMsec': now_ms - 1000})
         self.assertFalse(bazaar.verify_purchase(product_sku='sub', purchase_token='t', is_subscription=True).is_valid)