feat: housekeeping automation — auto-task on checkout + room status on done

Backend:
- Migration 023: housekeeping_settings table (checkout_auto, checkout_priority, inspection_after_clean)
- New route: GET/PATCH /api/hotels/:slug/housekeeping-settings
- bookings.ts: on checked_out → auto-create turnover task + mark room dirty + broadcast WS
- housekeeping.ts: on task done → update room status (inspect|clean per setting) + broadcast WS
- ws.ts: export broadcast() for use in other routes

Frontend:
- HousekeepingPage: load/save settings to API, live Loader on save button
- useHotelSocket: add housekeeping WS message types
- HousekeepingPage: subscribe to WS — new tasks appear instantly without refresh
- BookingModal: show total section when room + nights selected (not just when total > 0)

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

backend/src/app.ts

@@ -28,6 +28,7 @@ import tariffsRoutes       from './routes/tariffs'
 import ratePeriodsRoutes   from './routes/rate-periods'
 import rateOverridesRoutes from './routes/rate-overrides'
 import uploadRoutes        from './routes/upload'
+import housekeepingSettingsRoutes from './routes/housekeeping-settings'
 
 export async function buildApp() {
   const fastify = Fastify({
@@ -100,6 +101,7 @@ export async function buildApp() {
   await fastify.register(ratePeriodsRoutes)
   await fastify.register(rateOverridesRoutes)
   await fastify.register(uploadRoutes)
+  await fastify.register(housekeepingSettingsRoutes)
 
   return fastify
 }