estest

                size_t sent = total_sent;

                size_t empty_streak = 0;

                static constexpr size_t max_empty = 500;

                size_t pump_counter = 0;

                uint8_t lbuf[8];

                while (sent < content_length) {

                    if (++pump_counter % 4 == 0)

                    // Pump incoming on every iteration to keep flow

                    // control responsive for large transfers.

                    q->pumpIncoming();

                    ResponseEvent(*tr, h3tid, 0);

                                      << content_length << std::endl;

                            break;

                        }

                        // Sleep to let upstream produce data — mirrors

                        // H2's event-driven break-and-resume approach.

                        // Brief sleep to let upstream produce data.

                        // Use a short 1ms sleep instead of 10ms to

                        // avoid stalling large streaming transfers

                        // (e.g. images) over HTTP/3.

                        std::this_thread::sleep_for(

                            std::chrono::milliseconds(10));

                            std::chrono::milliseconds(1));

                    }

                }