fetchFarcasterChannelByName is a function that given a farcaster channel name, will retreive the info for that channel. The reason for this function is that we want to validate the user input given to us from the TagUnfollowedFarcasterChannel screen and confirm that the user inputted a valid channel name.
If the user inputted a channel name that does not exist, fetchFarcasterChannelByName will return null
Neynar API docs: https://docs.neynar.com/reference/search-channels
Linear task: https://linear.app/comm/issue/ENG-7471/add-the-search-channels-neynar-endpoint-to-our-neynar-api-client
We should prefer Array type