[native] add farcaster icon on native

Summary:
missed this in my previous diff stack. we need to add the farcaster icon to icons to make it available in the action sheet.

i also resized the ethereum-outline icon because it looked too small

Depends on D13475

Test Plan:
see attached photos. farcaster icon now appears in action sheet and the ethereum icon looks right

(simply replaced the icon name to test the ethereum icon size, not actually using that icon for the farcaster avatar option in action sheet)

Reviewers: will

Reviewed By: will

Subscribers: ashoat, tomek

Differential Revision: https://phab.comm.dev/D13476