* feat(cli): add archive command for cross-host data transport
* fix(archive): correct flat-layout path and entry-count wording
* refactor(archive): rename BuildArchive to WriteArchive
* refactor(cli): flatten keys export/import into dumpkeys/restore
The keys noun-group clashed with the flat dump/list verbs; unify on flat verbs and drop the keys parent. Pure rename, no behavior change.
* docs(rfc): add RFC-013 CLI redesign & cross-host restore
The accepted design doc for the flat-verb CLI redesign and cross-platform restore.