feat: 新增 RealnamePolicy 常量枚举及 CodeRealnameNotAvailable 错误码

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-openagent)

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>

pkg/errors/codes.go

@@ -151,6 +151,7 @@ const (
 	CodeOldPhoneMismatch        = 1186 // 旧手机号与当前绑定不匹配
 	CodeNeedRealname            = 1187 // 该套餐需实名认证后购买
 	CodeOpenIDNotFound          = 1188 // 未找到微信授权信息，请先完成授权
+	CodeRealnameNotAvailable    = 1189 // 请先完成充值或购买套餐后再进行实名认证
 
 	// 换货相关错误 (1200-1209)
 	CodeExchangeOrderNotFound      = 1200 // 换货单不存在
@@ -287,6 +288,7 @@ var allErrorCodes = []int{
 	CodeOldPhoneMismatch,
 	CodeNeedRealname,
 	CodeOpenIDNotFound,
+	CodeRealnameNotAvailable,
 	CodeExchangeOrderNotFound,
 	CodeExchangeInProgress,
 	CodeExchangeStatusInvalid,
@@ -418,6 +420,7 @@ var errorMessages = map[int]string{
 	CodeOldPhoneMismatch:                  "旧手机号与当前绑定不匹配",
 	CodeNeedRealname:                      "该套餐需实名认证后购买",
 	CodeOpenIDNotFound:                    "未找到微信授权信息，请先完成授权",
+	CodeRealnameNotAvailable:              "请先完成充值或购买套餐后再进行实名认证",
 	CodeExchangeOrderNotFound:             "换货单不存在或无权限",
 	CodeExchangeInProgress:                "该资产存在进行中的换货单",
 	CodeExchangeStatusInvalid:             "换货单当前状态不允许此操作",