feat(user): 新增iap支付

app/user/cmd/api/desc/pay.api

@@ -38,4 +38,7 @@ service main {
 	// 支付
 	@handler Payment
 	post /pay/payment (PaymentReq) returns (PaymentResp)
+
+	@handler IapCallback
+	post /pay/iap_callback (IapCallbackReq)
 }

app/user/cmd/api/desc/pay/pay.api

@@ -9,14 +9,19 @@ info (
 
 type (
 	PaymentReq {
-		Id string `json:"id"`
+		Id        string `json:"id"`
 		PayMethod string `json:"pay_method"`
 	}
 	PaymentResp {
 		prepayID string `json:"prepay_id"`
-		OrderID int64 `json:"order_id"`
+		OrderID  int64  `json:"order_id"`
 	}
 )
 
-
+type (
+	IapCallbackReq {
+		OrderID int64 `json:"order_id" validate:"required"`
+		TransactionReceipt string `json:"transaction_receipt" validate:"required"`
+	}
+)