Runtime and events

Application composes agents and stores. Runtime owns execution, cancellation, approvals, event ordering, and publication. Every state transition is a RuntimeEvent with a stable ID, UTC timestamp, session/run/trace relationships, JSON-safe payload, and monotonic session sequence.

Stores append an event before subscribers see it. A WebSocket reconnect sends its last sequence, replays later events, then follows the live stream. This makes the workspace a projection rather than the source of truth.