auth - fix login flow

[SKairinos]

The frontend needs to call the backend and successfully log in. This requires storing 2 session cookies, a http-only cookie a non-http-only cookie. The http-only cookie is needed to store the actual session secret for the user and must be http-only for security reasons. The non-http-only is needed to store the session's state, such as is there are any pending auth factors.

Finally, the Page component needs a property "auth" to determine whether or not the user is required to be authenticated to see that page.