fyi.opensocial.migrateExport

On the source host, for the destination of a move migratePrepare started: a part of the group nothing public serves whole. `meta` is what this host keeps of a space as its authority (whether anyone may read it, who writes there, and who may beyond its access record), as JSON, `repo` the group's own repo in a space (as com.atproto.space.getRepo does), `blobs` the list of its files and `blob` one of them. Authorized by migratePrepare's token, for an hour.