In firebase and identityserver I can easily setup policies that can detect if a user doesn't have an account then push them towards signup flow. Is there a way to do the same with B2C. Sample screenshots below. First is firebase, second is b2c. Currently all the example I've found have two separate paths, user tries to sign in, receives validation warning, then looks for signup button. You can see below how the firebase example is much simpler for the user.