Initial scaffold: tablet-checkin app

Staff-push guest check-in tablet. Fastify backend + React/Vite frontend,
three-tier auth (staff JWT, terminal API key, kiosk cookie), NewBook
integration via bookings_get/guests_update/bookings_update, pdfkit-based
regcard generation, marketing opt-in with Sendy/Mailchimp adapters.

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

frontend/src/types.ts

@@ -0,0 +1,140 @@
+export type DeviceStatus = 'idle' | 'busy'
+
+export interface Device {
+  device_id: string
+  name: string
+  status: DeviceStatus
+  last_seen: string | null
+  created_at: string
+}
+
+export interface Terminal {
+  terminal_id: string
+  name: string
+  created_at: string
+  last_used_at: string | null
+  revoked_at: string | null
+}
+
+export interface CreatedTerminal extends Terminal {
+  api_key: string // present only in the create response — never again
+}
+
+export type CheckinStatus = 'pending' | 'complete' | 'failed'
+
+export interface MarketingSyncSummary {
+  provider: string
+  status: 'pending' | 'success' | 'failed'
+  error: string | null
+}
+
+export interface Checkin {
+  id: number
+  booking_id: string
+  guest_id: string | null
+  hotel_id: string
+  device_id: string | null
+  device_name: string | null
+  guest_name: string | null
+  guest_email: string | null
+  pdf_path: string | null
+  opted_in: boolean
+  status: CheckinStatus
+  error: string | null
+  submitted_at: string
+  marketing_sync: MarketingSyncSummary[] | null
+}
+
+export type MarketingProviderId = 'sendy' | 'mailchimp'
+
+export interface SendyConfig {
+  api_key?: string
+  install_url?: string
+  list_id?: string
+}
+
+export interface MailchimpConfig {
+  api_key?: string
+  server_prefix?: string
+  audience_id?: string
+}
+
+export interface MarketingProvider {
+  provider: MarketingProviderId
+  active: boolean
+  config: SendyConfig | MailchimpConfig
+  updated_at: string
+  implemented: boolean
+}
+
+export interface MarketingSyncRow {
+  id: number
+  checkin_id: number
+  provider: string
+  status: 'pending' | 'success' | 'failed'
+  attempts: number
+  last_attempt_at: string | null
+  error: string | null
+  created_at: string
+  booking_id: string
+  guest_name: string | null
+  guest_email: string | null
+}
+
+export interface AppSettings {
+  newbook_hotel_id: string
+  regcard_custom_field_id: string
+  online_checkin_complete_custom_field_id: string
+  terms_and_conditions_text: string
+}
+
+// ── Guest-facing token flow (routes/checkin.js) ─────────────────────────────
+export interface CheckinBooking {
+  booking_id: string
+  arrival: string | null
+  departure: string | null
+  site_name: string | null
+  tariff_total: number | string | null
+  nights: number | null
+}
+
+export interface ExistingEmail {
+  content: string
+  is_relay: boolean
+}
+
+export interface CheckinGuest {
+  guest_id: string | null
+  name: string
+  address: string
+  phone: string
+  existing_emails: ExistingEmail[]
+  car_rego: string
+}
+
+export interface CheckinTokenData {
+  booking: CheckinBooking
+  guest: CheckinGuest
+  terms_text: string
+}
+
+export interface SubmitCheckinPayload {
+  email: string
+  car_rego: string
+  opted_in: boolean
+  accepted_terms: boolean
+  signature_png_base64: string
+}
+
+// ── Staff auth ──────────────────────────────────────────────────────────────
+export interface User {
+  user_id: number
+  name: string
+  email: string
+  is_admin: boolean
+  caps: string[] // bare slugs — verify?app=tablet-checkin strips the prefix
+}
+
+export function can(user: User, cap: string): boolean {
+  return user.is_admin || user.caps.includes(cap)
+}