feat: Passwordless cross-device authentication

- Arkitektur: docs/auth/passwordless-architecture.md
- Backend: iom/quixzoom-auth-service/ (FastAPI + Redis)
- Webb: quixzoom-market-pages/se/login/ (QR-kod + polling)
- App: iom/quixzoom-app/src/features/auth/ (push + deep links)

Flöde: QR-kod → app-godkännande → webb-inloggad

landvex/node_modules/validator/es/lib/toBoolean.js

@@ -0,0 +1,8 @@
+import assertString from './util/assertString';
+export default function toBoolean(str, strict) {
+  assertString(str);
+  if (strict) {
+    return str === '1' || /^true$/i.test(str);
+  }
+  return str !== '0' && !/^false$/i.test(str) && str !== '';
+}