Readonly
needsIndicates if the identity has changed in a way that needs user approval.
This happens if the identity has changed since we first saw it, unless the new identity has also been verified by our user (eg via an interactive verification).
To rectify this, either:
true if this user is verified via cross signing
true if this user is verified via any means
true if we ever verified this user before (at least for the history of verifications observed by this device).
Represents the ways in which we trust a user