8b6d326824
Adds an env2-owned HTTP sink container (scadabridge-env2-sfsink) whose 503 mode makes ExternalSystem.CachedCall buffer, and an EnvSoak template whose 2 s SoakTick sends one tick-numbered cached call, so loss and duplicates are countable at the sink. Claude-Session: https://claude.ai/code/session_01GT67ACmpMR7b9LGRPLijMi