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>

config/health.py

@@ -118,6 +118,7 @@ def _check_integrations() -> dict:
         'openai': bool(getattr(settings, 'OPENAI_API_KEY', '')),
         'sms': bool(getattr(settings, 'KAVENEGAR_API_KEY', '')),
         'bazaar': _bazaar_configured(),
+        'bazaarDynamicPrice': bool(getattr(settings, 'BAZAAR_DYNAMIC_PRICE_KEY', '')),
         'aiProvider': _ai_provider_state(),
         'chatModel': getattr(settings, 'OPENAI_CHAT_MODEL', ''),
         'chatModelUpper': getattr(settings, 'OPENAI_CHAT_MODEL_UPPER', '') or None,