fix(loyalty): fix runtime bugs in storefront routes, point expiration, and enforce settings

- Add total_points_voided column to LoyaltyCard with migration (loyalty_002)
- Fix storefront self_enroll to use correct service method signature and schema fields
- Fix get_my_card/get_my_transactions to use get_card_by_customer_and_merchant
- Fix transaction history field reference (balance_after -> points_balance_after)
- Fix point_expiration task: wrong field names and manual balance update -> card.expire_points()
- Register storefront_router in definition.py and export all routers from __init__.py
- Enforce MerchantLoyaltySettings in storefront enrollment, points, and stamp void operations
- Fix test fixture using non-existent balance_after column
- Suppress intentional architecture validator warnings in templates

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

tests/fixtures/loyalty_fixtures.py

@@ -139,7 +139,7 @@ def test_loyalty_transaction(db, test_loyalty_card, test_store):
         store_id=test_store.id,
         transaction_type=TransactionType.POINTS_EARNED.value,
         points_delta=50,
-        balance_after=150,
+        points_balance_after=150,
         stamps_delta=0,
         stamps_balance_after=0,
         notes="Test purchase",