Add @fastify/websocket. EventLog fires an onAppended callback after each durable
append; device-events gains a ledger channel (emitLedger). /api/ws fans out
ledger + occupancy + printer-status to authenticated booth clients. Origin
allowlist (WS_ALLOWED_ORIGINS) replaces CSRF for the handshake (anti-CSWSH).
Note: server.ts also reflects later booth route wiring; the final HEAD builds.
julian
c2f06a5d2a