[native] remove useQRAuth hook

Summary:
ENG-8385.

QR code login is not working right now. As described here (Point 3) and here the issue is occuring because of the fact that useQRAuth is unmounting before it can send SECONDARY_DEVICE_REGISTRATION_SUCCESS. This stack is refactoring the code to move logic to context (see here).

Moving this code to a context - reduces some complexity.

Depends on D12452

Test Plan: Test QR login flow on native and web. Adding a bunch of logs to make sure it works and all messages are sent.

Reviewers: bartek, ashoat

Reviewed By: bartek, ashoat

Subscribers: ashoat, tomek

Differential Revision: https://phab.comm.dev/D12453