Measure: turns per exchange, native vs hub (send -> receive -> reply -> receive)

SENDMESS-3 sendmessage Done high ↳ SENDMESS-1

Measure: tokens per delivery, native vs hub (same message, same pair, N=10 each way)

SENDMESS-2 sendmessage Done high ↳ SENDMESS-1

Measure: context-window cost of having native messaging enabled at all (schema/idle overhead)

SENDMESS-5 sendmessage Done ↳ SENDMESS-1

Measure: end-to-end latency idle vs busy receiver, native vs hub, with LLMMSG_POLL_MS=1000 as a third arm

SENDMESS-4 sendmessage Done ↳ SENDMESS-1