Group
A generic membership/capability snapshot for a group.
Reports raw facts rather than answers. For the proposal (app-data-dictionary) migration specifically: to ask whether the group is already migrated, prefer org.xmtp.android.library.Group.proposalsEnabled over scanning contextExtensions for MlsExtensionType.AppDataDictionary. The snapshot's job is eligibility: the group can migrate when every installation's InstallationCapabilities.supportedExtensions contains that extension, and the inboxes blocking migration are those with an installation that doesn't.
Read it with org.xmtp.android.library.Group.membershipCapabilities; drive the upgrade with org.xmtp.android.library.UnstableGroup.enableProposals (via group.unstable, opting in with @OptIn(UnstableApi::class)).