Fix ws.ts: use SocketStream from @fastify/websocket v8

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

backend/src/routes/ws.ts

@@ -1,36 +1,37 @@
 import { FastifyPluginAsync } from 'fastify'
 import fastifyWebsocket from '@fastify/websocket'
-import type { WebSocket, RawData } from 'ws'
+import type { SocketStream } from '@fastify/websocket'
+import type { RawData } from 'ws'
 
-// hotel slug → set of connected clients
-const hotelRooms = new Map<string, Set<WebSocket>>()
+// hotel slug → set of connected streams
+const hotelRooms = new Map<string, Set<SocketStream>>()
 
 const ws: FastifyPluginAsync = async (fastify) => {
   await fastify.register(fastifyWebsocket)
 
-  fastify.get<{ Querystring: { hotel?: string; token?: string } }>(
+  fastify.get<{ Querystring: { hotel?: string } }>(
     '/ws',
     { websocket: true },
-    (socket, request) => {
-      const hotel = request.query.hotel ?? ''
-      if (!hotel) { socket.close(4001, 'hotel required'); return }
+    (connection: SocketStream, request) => {
+      const hotel = (request.query as { hotel?: string }).hotel ?? ''
+      if (!hotel) { connection.socket.close(4001, 'hotel required'); return }
 
       if (!hotelRooms.has(hotel)) hotelRooms.set(hotel, new Set())
-      hotelRooms.get(hotel)!.add(socket)
+      hotelRooms.get(hotel)!.add(connection)
 
-      socket.on('message', (raw: RawData) => {
+      connection.socket.on('message', (raw: RawData) => {
         const data = raw.toString()
         const peers = hotelRooms.get(hotel)
         if (!peers) return
-        peers.forEach(client => {
-          if (client !== socket && client.readyState === 1) {
-            client.send(data)
+        peers.forEach(peer => {
+          if (peer !== connection && peer.socket.readyState === 1) {
+            peer.socket.send(data)
           }
         })
       })
 
-      socket.on('close', () => {
-        hotelRooms.get(hotel)?.delete(socket)
+      connection.socket.on('close', () => {
+        hotelRooms.get(hotel)?.delete(connection)
         if (hotelRooms.get(hotel)?.size === 0) hotelRooms.delete(hotel)
       })
     },