[native] Make Farcaster required in new registration flow

Summary:
Only making it required on release builds to avoid making testing more difficult for devs.

Depends on D11973

Test Plan: Replaced usage of __DEV__ with a hardcoded variable. Tested opening the registration flow from the main screen and from FullscreenSIWEPanel. Make sure CoolOrNerdModeSelection and KeyserverSelection don't appear. Make sure that I am able to successfully register

Reviewers: ginsu, inka

Reviewed By: ginsu

Subscribers: tomek

Differential Revision: https://phab.comm.dev/D11974