fix(protocol): reject incompatible orchestration peers

Advertise and validate an explicit orchestration protocol before clients open RPC sessions. Announce the same protocol on WebSocket upgrades so hosts reject older clients before request decoding while preserving existing auth and relay parameters.

Audit: D03

Implemented by GPT-5.6 Sol with Codex.
4b84a36844Julius Marminge committed on 9/1/2026, 4:32:53 AMparent7ef335b
15 files changedLine totals unavailable