refactor(automations): detect manual payment via OrderTransaction.manualPaymentGateway

- Drop wireTransferGatewayNames from ShopSettings (new migration).
- Replace string-matching with a GraphQL query against
  Order.transactions[].manualPaymentGateway, the first-class flag
  Shopify exposes for any merchant-defined manual payment method.
- Both webhook handlers now fetch the order on the fly to classify it,
  removing the configurable gateway-names field from settings.

prisma/migrations/20260512130000_drop_wire_transfer_gateway_names/migration.sql

@@ -0,0 +1,4 @@
+-- Drop the column added by the previous migration; we now classify
+-- wire-transfer orders by querying OrderTransaction.manualPaymentGateway
+-- via the GraphQL Admin API instead of by configurable name match.
+ALTER TABLE "ShopSettings" DROP COLUMN "wireTransferGatewayNames";