Baseline — single big file (HTTP/2)

This page is served over HTTP/2 on port 443 (Caddy default). It tries to fetch() a single 1 MiB binary blob, also on port 443.

Expected: TSPU caps a single TCP connection at ~16 KiB. The fetch will stall after ~16 KiB and eventually time out.

Compare with the chunked-delivery solution: https://reg.soon.it:8443/demo-chunked.html