refactor(group): update user group handling to utilize userUsableGroups directly and add GetUserGroupRatio function

service/group.go

@@ -52,3 +52,14 @@ func GetUserAutoGroup(userGroup string) []string {
 	}
 	return autoGroups
 }
+
+// GetUserGroupRatio 获取用户使用某个分组的倍率
+// userGroup 用户分组
+// group 需要获取倍率的分组
+func GetUserGroupRatio(userGroup, group string) float64 {
+	ratio, ok := ratio_setting.GetGroupGroupRatio(userGroup, group)
+	if ok {
+		return ratio
+	}
+	return ratio_setting.GetGroupRatio(group)
+}