feat: add confluence/slack search tools, chat history, cloud Qdrant support, sync trigger fixes

feat: channel RBAC through ingest, graph stream, admin endpoints, email invite

Fix WebSocket stream: use result.data() instead of async for to match working traverse pattern

Add retry-on-SessionExpired for ingest writes; fix WebSocket driver init error handling

Fix chunk relationship injection and WebSocket close handling

Fix defunct Neo4j connection: add keep-alive, liveness check, retry on SessionExpired

Add Neo4j graph stream WebSocket endpoint for live visualization