[native] build out UI for farcaster account settings screen

Summary:
This diff further extends the farcaster account settings screen by implmenting the UI for this screen. To make sure this diff was not too difficult to review, I broke this diff up into two where the next diff will handle unauthing from farcaster

Depends on D11484

Test Plan:
Please see the screenshots below + tested the entire sign in + unauth flow during the hackathon

not connected to farcaster:

connected to farcaster:

Reviewers: atul

Reviewed By: atul

Subscribers: ashoat, tomek

Differential Revision: https://phab.comm.dev/D11512