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/slash/index.d.ts

@@ -0,0 +1,25 @@
+/**
+Convert Windows backslash paths to slash paths: `foo\\bar` ➔ `foo/bar`.
+
+[Forward-slash paths can be used in Windows](http://superuser.com/a/176395/6877) as long as they're not extended-length paths and don't contain any non-ascii characters.
+
+@param path - A Windows backslash path.
+@returns A path with forward slashes.
+
+@example
+```
+import * as path from 'path';
+import slash = require('slash');
+
+const string = path.join('foo', 'bar');
+// Unix    => foo/bar
+// Windows => foo\\bar
+
+slash(string);
+// Unix    => foo/bar
+// Windows => foo/bar
+```
+*/
+declare function slash(path: string): string;
+
+export = slash;