Add a client setting around UV boolean on `preferred`

[Progdrasil]

Suggestion(follow-up): So this would put uv = true on preferred and required. This may not be true for other providers, they may want to do UV only on required for example. This should be a setting on the client that can be enabled. Not a blocking issue for this PR, I'm mainly adding this to create a follow-up issue about it.

Originally posted by @Progdrasil in https://github.com/1Password/passkey-rs/pull/22#discussion_r1633616876