http-adapters.md: forwarding-handler step 5 documents the time/bytes
split for Sub forwards (stream client without the total request
timeout, total streamed-bytes cap, read timeout as the staleness
guard); the HTTP Client section documents the two derived clients
(request vs stream), the reqwest 0.13 per-request-override limitation
that forces the derived-client design, and that only the total timeout
differs between them.
http-server.md: the per-endpoint dispatch deadline paragraph now covers
the outbound half — unbounded time, bounded bytes on both the gateway
and the forwarding side (ADR-049/021 note: unbounded time by design for
subscriptions, bounded bytes per subscription).
Verified: cargo doc --no-deps clean, full suite green.