[native] navigate to proper screen after scanning QR code

Summary:
ENG-9959.

Navigates to screen implemented in previous diffs in the stack, right after the QR code is scanned.

Adds useFocusEffect because after swiping back to the camera user should be able to scan the QR again.

In ENG-9968 there is an example of how this flow looks like

Depends on D14115

Test Plan:
Test this on both secondary and primary, full flow should work.

After swiping back to the camera, the user can scan the QR code again.

Reviewers: ashoat, tomek

Reviewed By: ashoat

Differential Revision: https://phab.comm.dev/D14116