fix: add card detail and store transactions endpoints for loyalty terminal

- Fix GET /cards/{card_id} 500 error (program_type → loyalty_type)
- Add GET /transactions endpoint for store-wide recent transactions
- Add get_store_transactions service method (merchant-scoped, store-filterable)

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

app/modules/loyalty/services/card_service.py

@@ -640,6 +640,31 @@ class CardService:
 
         return transactions, total
 
+    def get_store_transactions(
+        self,
+        db: Session,
+        merchant_id: int,
+        *,
+        store_id: int | None = None,
+        skip: int = 0,
+        limit: int = 10,
+    ) -> tuple[list[LoyaltyTransaction], int]:
+        """Get recent transactions for a merchant (optionally filtered by store)."""
+        query = (
+            db.query(LoyaltyTransaction)
+            .join(LoyaltyCard, LoyaltyTransaction.card_id == LoyaltyCard.id)
+            .options(joinedload(LoyaltyTransaction.store))
+            .filter(LoyaltyCard.merchant_id == merchant_id)
+        )
+        if store_id:
+            query = query.filter(LoyaltyTransaction.store_id == store_id)
+
+        query = query.order_by(LoyaltyTransaction.transaction_at.desc())
+        total = query.count()
+        transactions = query.offset(skip).limit(limit).all()
+
+        return transactions, total
+
     def get_customer_transactions_with_store_names(
         self,
         db: Session,