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/ltrim.js

@@ -0,0 +1,7 @@
+import assertString from './util/assertString';
+export default function ltrim(str, chars) {
+  assertString(str);
+  // https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Regular_Expressions#Escaping
+  var pattern = chars ? new RegExp("^[".concat(chars.replace(/[.*+?^${}()|[\]\\]/g, '\\$&'), "]+"), 'g') : /^\s+/g;
+  return str.replace(pattern, '');
+}