refactor: rename iot client to stateless gateway

backend/api/internal/config/config.go

@@ -66,10 +66,9 @@ type PaymentConfig struct {
 	Wechat               WechatPayConfig `yaml:"Wechat"`
 }
 
-// IoTConfig 保存 API、Worker 与 IoT Client 间的内部认证和地址。
+// IoTConfig 保存 API 与 IoT 链路间的内部认证配置。
 type IoTConfig struct {
 	InternalServiceToken string `yaml:"InternalServiceToken"`
-	ClientBaseURL        string `yaml:"ClientBaseURL"`
 }
 
 // SrvConfig 与仓库现有进程的配置结构保持一致。
@@ -110,8 +109,8 @@ func New(srvKey string) {
 	if Spec.Payment.ExpireMinutes <= 0 || Spec.Payment.RefundWindowDays <= 0 {
 		panic("Payment expiration and refund window must be greater than zero")
 	}
-	if len(strings.TrimSpace(Spec.IoT.InternalServiceToken)) < 16 || !strings.HasPrefix(Spec.IoT.ClientBaseURL, "http") {
-		panic("IoT internal token and client base URL are required")
+	if len(strings.TrimSpace(Spec.IoT.InternalServiceToken)) < 16 {
+		panic("IoT internal token is required")
 	}
 	registerURL, err := url.ParseRequestURI(Spec.Global.UserRegisterURL)
 	if err != nil || (registerURL.Scheme != "http" && registerURL.Scheme != "https") || registerURL.Host == "" {