Dify

• 启用企业版才有的大模型负载均衡功能：在api/services/feature_service.py文件中新增一行（https://github.com/brightwang/dify-model-lb）：

  class FeatureService:
      @classmethod
      def get_features(cls, tenant_id: str) -> FeatureModel:
          features = FeatureModel()
          cls._fulfill_params_from_env(features)
          if dify_config.BILLING_ENABLED:
              cls._fulfill_params_from_billing_api(features, tenant_id)
          # 新增此行
          features.model_load_balancing_enabled = True
          return features