Add kiosk wall-panel control view

Full-screen /kiosk route, separate from the staff SPA: dedicated long-lived
kiosk login (own password, hashed, mints its own hnf_session cookie locally
via CENTRAL_AUTH_SECRET -- no central auth changes needed), scrollable grid
of small mode/setpoint blocks per live-controllable device (shelly_trv,
mhi_mqtt, daikin), tap-to-edit modal reusing the existing per-type control
panels, and a type-aware bulk multiselect (separate TRV/AC sections, only
applied to matching selected devices, TRV commands staggered).

- backend/src/routes/kiosk.js: public POST /api/kiosk/login
- backend/src/routes/settings.js: admin set/check kiosk password (bcrypt)
- backend/src/routes/config.js: exclude/protect kiosk_password_hash
- frontend/src/pages/Kiosk.tsx + components/Kiosk*: the kiosk UI
- reuses GET /api/status for the combined device list -- no new status
  endpoint needed since the kiosk token now also carries the 'view' cap

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

backend/package.json

@@ -11,6 +11,7 @@
     "@fastify/cors": "^9.0.1",
     "@fastify/multipart": "^8.3.0",
     "@fastify/static": "^7.0.4",
+    "bcryptjs": "^2.4.3",
     "fastify": "^4.28.1",
     "jose": "^5.9.6",
     "luxon": "^3.5.0",