Add Guests module: API integration + passport identification

- Migration 009: add passport_series, passport_number, rating to guests table
- Backend route /api/hotels/:slug/guests: list, get (with history), create/upsert by passport, update, delete
- Frontend GuestsPage: loads from API, passport tab in modal, add guest form, search by passport
- api.ts: add guests API methods and GuestApiType

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

backend/src/app.ts

@@ -16,6 +16,7 @@ import housekeepingRoutes from './routes/housekeeping'
 import channelsRoutes    from './routes/channels'
 import usersRoutes       from './routes/users'
 import netupRoutes       from './routes/netup'
+import guestsRoutes      from './routes/guests'
 
 export async function buildApp() {
   const fastify = Fastify({
@@ -73,6 +74,7 @@ export async function buildApp() {
   await fastify.register(channelsRoutes)
   await fastify.register(usersRoutes)
   await fastify.register(netupRoutes)
+  await fastify.register(guestsRoutes)
 
   return fastify
 }