feat: initial work unifying new endpoint and generating api key

lib/validations/payment.ts

@@ -2,9 +2,9 @@ import { withValidation } from "next-validations";
 
 import { _PaymentModel as Payment } from "@calcom/prisma/zod";
 
+// FIXME: Payment seems a delicate endpoint, do we need to remove anything here?
 export const schemaPaymentBodyParams = Payment.omit({ id: true });
-
-export const schemaPaymentPublic = Payment.omit({});
+export const schemaPaymentPublic = Payment.omit({ externalId: true });
 
 export const withValidPayment = withValidation({
   schema: schemaPaymentBodyParams,