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

node_modules/iconv-lite/lib/helpers/merge-exports.js

@@ -0,0 +1,13 @@
+"use strict"
+
+var hasOwn = typeof Object.hasOwn === "undefined" ? Function.call.bind(Object.prototype.hasOwnProperty) : Object.hasOwn
+
+function mergeModules (target, module) {
+  for (var key in module) {
+    if (hasOwn(module, key)) {
+      target[key] = module[key]
+    }
+  }
+}
+
+module.exports = mergeModules