Implement REQUIRE_INTERACTIVE policy
Created by: olabini
If this policy is turned on, the library will not start a DAKE using non-interactive auth - it will only allow for DAKEZ and online conversation initiation. This should be possible to configure in the UI as well.
(There is a question here about what we do if we RECEIVE a non-interactive auth. Do we drop it? Should we have a different policy for that? This should be investigated and decided). (Another question is whether we should have policies for whether to publish prekey messages and other things, or if that behavior is controlled some other way)