fix(订单折扣): 将折扣计算从整数百分比改为浮点数

修改 SubscribeDiscount 结构体中的 Discount 字段类型为 float64，并调整 getDiscount 函数逻辑以直接使用浮点数计算

internal/logic/public/order/getDiscount.go

@@ -2,8 +2,11 @@ package order
 
 import "github.com/perfect-panel/server/internal/types"
 
+// getDiscount 计算最终价格倍数
+// 参数：discounts 折扣规则列表（数量阈值 + 折扣倍数）；inputMonths 购买时长
+// 返回：最终价格倍数（如 0.95 表示按 95% 计价）
 func getDiscount(discounts []types.SubscribeDiscount, inputMonths int64) float64 {
-	var finalDiscount int64 = 100
+	var finalDiscount float64 = 1.0
 
 	for _, discount := range discounts {
 		if inputMonths >= discount.Quantity && discount.Discount < finalDiscount {
@@ -11,5 +14,5 @@ func getDiscount(discounts []types.SubscribeDiscount, inputMonths int64) float64
 		}
 	}
 
-	return float64(finalDiscount) / float64(100)
+	return finalDiscount
 }

internal/types/types.go

@@ -2084,8 +2084,8 @@ type SubscribeConfig struct {
 }
 
 type SubscribeDiscount struct {
-	Quantity int64 `json:"quantity"`
-	Discount int64 `json:"discount"`
+	Quantity int64   `json:"quantity"`
+	Discount float64 `json:"discount"`
 }
 
 type SubscribeGroup struct {