a3f29e6eb9
Adds ChatTurnEvent (role USER|ROUTER) so router conversation history survives restart and is rebuilt from the event log via projection, restoring Hard Invariant #1 for the CHAT path. Both CHAT and STEERING now emit user + router turn events; STEERING additionally keeps its existing SteeringNoteAddedEvent so the structured directive record is preserved alongside the conversation turns. RouterFacade drops the in-memory ConcurrentHashMap of histories and rebuilds state through the repository after each emission. Reducer appends turns to conversationHistory. ChatTurnEvent is registered in eventModule.