Auto-suggest name for new Passkeys

- Use plain client data json everywhere
- Expose AAGUID and backed_up on Credentials
- Make attestation verifiers configurable
- Auto-suggest names for passkeys and show icons

app/controllers/concerns/current_request.rb

@@ -10,6 +10,7 @@ module CurrentRequest
       Current.referrer    = request.referrer
 
       ActionPack::WebAuthn::Current.host = request.host
+      ActionPack::WebAuthn::Current.origin = request.base_url
     end
   end
 end