cairn/changes/wizard-capability-auth-probe/tasks.md
available_auth_mechanisms to io-imap's coroutine core (rfc3501::capability), reusing pimalaya-stream's SaslMechanism (ordered by preference, LOGIN last, honours LOGINDISABLED); pull pimalaya-stream minimally as a non-optional dep so it is not TLS-provider gatedcompose_all_within in io-pim-discovery and call it from the wizard