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.

app/routes/app.settings.tsx

@@ -177,7 +177,6 @@ export const action = async ({ request }: ActionFunctionArgs) => {
     emailBodyHtmlEn: str("emailBodyHtmlEn"),
     autoEmailOnWireTransferPlaced: bool("autoEmailOnWireTransferPlaced"),
     autoEmailOnFulfilledNonWireTransfer: bool("autoEmailOnFulfilledNonWireTransfer"),
-    wireTransferGatewayNames: str("wireTransferGatewayNames"),
   };
 
   await db.shopSettings.upsert({
@@ -422,8 +421,10 @@ export default function SettingsRoute() {
               Flow required (Flow is gated to Plus stores for custom apps).
               When an automation fires, the invoice is generated (if it doesn't
               already exist) and emailed to the customer using the SMTP and
-              email-template settings above. A copy is recorded in the email
-              log; failures are logged server-side.
+              email-template settings above. "Wire-transfer" is detected via
+              Shopify's <code>OrderTransaction.manualPaymentGateway</code> flag,
+              so any merchant-defined manual payment method (Überweisung, Cash
+              on Delivery, Money Order, …) qualifies.
             </s-paragraph>
             <Toggle
               label='Auto-email the invoice when a wire-transfer order is placed (so the customer gets the bank details + GiroCode immediately).'
@@ -435,12 +436,6 @@ export default function SettingsRoute() {
               name="autoEmailOnFulfilledNonWireTransfer"
               checked={settings.autoEmailOnFulfilledNonWireTransfer}
             />
-            <Field
-              label="Wire-transfer payment gateway names (comma-separated, case-insensitive substring match)"
-              name="wireTransferGatewayNames"
-              defaultValue={settings.wireTransferGatewayNames}
-              helpText='Used to classify which orders count as "wire transfer". Leave empty to use the default: manual, Überweisung, Wire Transfer, Bank Transfer, Vorkasse, Bank Deposit.'
-            />
           </s-stack>
         </s-section>