重构代码结构，迁移Baiyin SDK相关逻辑至globals包，并添加支付宝客户端初始化

web/handlers/trade.go

@@ -1,13 +1,16 @@
 package handlers
 
 import (
+	"net/url"
 	"platform/web/auth"
+	g "platform/web/globals"
 	m "platform/web/models"
 	q "platform/web/queries"
 	"platform/web/services"
 	"strconv"
 
 	"github.com/gofiber/fiber/v2"
+	"github.com/smartwalle/alipay/v3"
 )
 
 // region CreateTrade
@@ -83,4 +86,31 @@ func CreateTrade(c *fiber.Ctx) error {
 	return nil
 }
 
+func createTradeByAlipay() (*url.URL, error) {
+
+	target, err := g.Alipay.TradePagePay(alipay.TradePagePay{
+		Trade:       alipay.Trade{},
+		AuthToken:   "",
+		QRPayMode:   "",
+		QRCodeWidth: "",
+	})
+	if err != nil {
+		return nil, err
+	}
+
+	return target, nil
+}
+
+func createTradeByWechat() error {
+	panic("unimplemented")
+}
+
+// endregion
+
+// region TradeCallbackAlipay
+
+// endregion
+
+// region TradeCallbackWechat
+
 // endregion