[fix] qr code scanner bug fixes (#80)

* address bug bash bugs

* move to expo-camera, set border colors

* [refactor] move QRCodeScanner/ to become a separate tab bar item.

* [feat] replace bottom tab bell with scanner icon.

* [feat] removed previous camera button from AllCases screen.

* [feat] configure addCase to route to the AllCases screen.

* [wip] working to refactor the qr scanner for usability.

* [feat] debounce invalid case feedback.

* [feat] debounce now applied to scanning valid cases.

* [refactor] cleanup new qr scanner logic.

* [feat] retrigger scanned animation each time a new case is scanned to improve usability.

* [feat] round camera viewport, hide case preview after joining case, hide view case option after navigating to a different screen.

* [cleanup] delete old AddCase folder.

* [cleanup] delete comments.

* [cleanup] rename debounced function name.

---------

Co-authored-by: Ronnie Beggs <[email protected]>