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/merge-descriptors/index.d.ts

@@ -0,0 +1,11 @@
+/**
+Merges "own" properties from a source to a destination object, including non-enumerable and accessor-defined properties. It retains original values and descriptors, ensuring the destination receives a complete and accurate copy of the source's properties.
+
+@param destination - The object to receive properties.
+@param source - The object providing properties.
+@param overwrite - Optional boolean to control overwriting of existing properties. Defaults to true.
+@returns The modified destination object.
+*/
+declare function mergeDescriptors<T, U>(destination: T, source: U, overwrite?: boolean): T & U;
+
+export = mergeDescriptors;