Fix NewBook write mechanism, bundle push extension, remove vestigial hotel_id

- setBookingCustomFields: use bookings_update's own custom_fields array
  (confirmed from the real legacy plugin code) instead of
  instance_custom_fields_set, which was only ever proven for a different,
  unrelated plugin
- online_checkin_complete is now a configurable per-hotel custom field
  (online_checkin_complete_custom_field_id setting), not a bogus top-level
  bookings_update field NewBook would silently ignore
- Fix field-name mismatches vs a real live NewBook booking response:
  booking_arrival/departure/length, guest address (street/city/state/
  postcode/country, not a single field), phone/mobile (in contact_details,
  not top-level), and pickPrimaryGuest now checks primary_client (was
  checking fields that don't exist in the real API)
- Bundle the standalone push extension into backend/extension-src/, add
  GET /api/extension/download (zips on request via archiver) and a
  download button on the Settings page
- Remove newbook_hotel_id — vestigial from the legacy system's multi-hotel
  routing model, never actually reached NewBook's API, this stack is
  single-hotel-per-deployment so there's nothing to route between

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

backend/src/db.js

@@ -120,7 +120,6 @@ export async function initDb() {
 }
 
 const SETTINGS_DEFAULTS = {
-  newbook_hotel_id: '',
   regcard_custom_field_id: '',
   online_checkin_complete_custom_field_id: '',
   kiosk_password_hash: '',

backend/src/index.js

@@ -10,6 +10,7 @@ import { checkinsRoutes } from './routes/checkins.js'
 import { marketingRoutes } from './routes/marketing.js'
 import { settingsRoutes } from './routes/settings.js'
 import { kioskRoutes } from './routes/kiosk.js'
+import { extensionRoutes } from './routes/extension.js'
 
 const app = Fastify({ logger: true, trustProxy: true })
 const startedAt = Date.now()
@@ -30,6 +31,7 @@ await app.register(checkinsRoutes)
 await app.register(marketingRoutes)
 await app.register(settingsRoutes)
 await app.register(kioskRoutes)
+await app.register(extensionRoutes)
 
 try {
   await initDb()

backend/src/lib/push.js

@@ -1,5 +1,5 @@
 import { randomBytes } from 'crypto'
-import { pool, getSetting } from '../db.js'
+import { pool } from '../db.js'
 import { pushNavigate } from './device-stream.js'
 
 const SESSION_TTL_MINUTES = 30
@@ -24,7 +24,14 @@ export async function pushBookingToDevice(deviceId, bookingId) {
     return { ok: false, status: 409, error: `${existing[0].name} is busy with another check-in` }
   }
 
-  const hotelId = (await getSetting('newbook_hotel_id', '')) || process.env.NEWBOOK_LOCATION_ID || ''
+  // Single-hotel-per-stack deployment (see project_checkin memory) — no
+  // per-request "which hotel" lookup needed, this whole app instance already
+  // is one hotel. hotel_id here is purely a local audit-row label, sourced
+  // from the same env var lib/newbook.js sends to the NewBook API itself
+  // (not a separate app-level setting — a local `newbook_hotel_id` Settings
+  // field existed here before 2026-09-01 but was removed as vestigial
+  // multi-hotel-model plumbing that no longer did anything real).
+  const hotelId = process.env.NEWBOOK_LOCATION_ID || ''
   const token = randomBytes(24).toString('hex')
   const expiresAt = new Date(Date.now() + SESSION_TTL_MINUTES * 60 * 1000)
 

backend/src/routes/extension.js

@@ -0,0 +1,39 @@
+import path from 'path'
+import { fileURLToPath } from 'url'
+import archiver from 'archiver'
+import { requireAuth, requireCap } from '../auth.js'
+
+const __dirname = path.dirname(fileURLToPath(import.meta.url))
+// Bundled copy of tablet-checkin-push (~/dev/HNF-PROXMOX/tablet-checkin-push),
+// baked into this image at build time (see Dockerfile) so the extension ships
+// with the app rather than needing separate distribution. Zipped fresh on
+// each request rather than a pre-built static file — small folder, cheap to
+// zip, and always reflects whatever's actually deployed (no separate
+// "remember to rebuild the zip" step to forget). See project_checkin memory's
+// "Standalone push extension" section.
+const EXTENSION_SRC = path.join(__dirname, '..', '..', 'extension-src')
+
+export async function extensionRoutes(app) {
+  // Gated the same as the Settings page it's linked from — any staff who can
+  // see Settings can download this, nothing sensitive lives in the extension
+  // itself (the terminal API key is entered by whoever installs it, not
+  // baked in here).
+  app.get('/api/extension/download', { preHandler: [requireAuth, requireCap('settings')] }, async (req, reply) => {
+    reply.header('Content-Type', 'application/zip')
+    reply.header('Content-Disposition', 'attachment; filename="tablet-checkin-push.zip"')
+
+    const archive = archiver('zip', { zlib: { level: 9 } })
+    archive.on('error', err => {
+      app.log.error(`[extension] zip stream error: ${err.message}`)
+      reply.raw.destroy(err)
+    })
+    // Root the zip's contents at "tablet-checkin-push/" rather than dumping
+    // files at the archive root — so extracting it doesn't scatter files
+    // into whatever folder the user unzipped into.
+    archive.directory(EXTENSION_SRC, 'tablet-checkin-push')
+
+    reply.hijack()
+    archive.pipe(reply.raw)
+    await archive.finalize()
+  })
+}

backend/src/routes/settings.js

@@ -9,7 +9,7 @@ import { testConnection } from '../lib/newbook.js'
 // readable back to the browser, only settable via its own dedicated route
 // below (mirrors hvac's Settings -> Kiosk pattern).
 const ALLOWED_KEYS = [
-  'newbook_hotel_id', 'regcard_custom_field_id', 'online_checkin_complete_custom_field_id',
+  'regcard_custom_field_id', 'online_checkin_complete_custom_field_id',
   'terms_and_conditions_text',
 ]