A body that stopped arriving held one of the receive slots (#47) and a spool file indefinitely. Every read of the upload body now pushes the connection read deadline UploadIdleTimeout (default 60 s) ahead, so a stalled body fails its read, Accept returns and the slot is released, while a slow but moving body is never cut (ReadTimeout would cut it). Two things found by running it over a socket: - metrics.statusWriter had no Unwrap, so http.ResponseController could not reach the connection and the bound silently did not apply in the production handler stack. It now unwraps; a writer that still cannot set a deadline logs "upload idle bound unavailable". - clearing the deadline on any read error left net/http's pre-reply drain of the unread remainder unbounded, so the connection hung. The deadline is now cleared only on a clean io.EOF. ADR-033 limitation amended. A 1-byte-per-59-s drip is still unbounded. Closes #56 Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>