feat: add WiFi authorization module

- Backend: hotel_wifi_settings table (migration 046), CRUD routes
- Public API endpoint /api/wifi-auth/verify for captive portal
- Auth methods: room+lastname, room+birthdate, room+any, room_only
- Frontend: WiFiPage with settings, token management, setup guide
- Guide tabs: MikroTik, UniFi, Universal with copy-paste instructions
- Sidebar: WiFi item in Settings group

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

backend/src/app.ts

@@ -36,6 +36,7 @@ import loyaltyRoutes       from './routes/loyalty'
 import chatRoutes          from './routes/chat'
 import workstationRoutes   from './routes/workstations'
 import agentReleaseRoutes  from './routes/agent-release'
+import wifiSettingsRoutes, { wifiAuthVerify } from './routes/wifi-settings'
 import { setupAgentWsRoute } from './agent-ws'
 import { startJobs } from './jobs'
 
@@ -123,6 +124,8 @@ export async function buildApp() {
   await fastify.register(chatRoutes)
   await fastify.register(workstationRoutes)
   await fastify.register(agentReleaseRoutes)
+  await fastify.register(wifiSettingsRoutes)
+  await fastify.register(wifiAuthVerify)
   await fastify.register(setupAgentWsRoute)
 
   startJobs()