The workspace family owns the persistent workspace concept: a directory the user works in, with a title and the ordered list of sessions that belong to it. Design record: domain KV storage Agent Note.

Package	Role	ctx key
`workspace/`	`WorkspaceRegistry` service over the storage domain form: realpath-unique paths, session-ownership accounting, entity cache	`ctx.workspace`

Ownership truth lives in the workspace record's sessionIds (ordered), never derived from session cwd; attachSession verifies the session header's cwd resolves to the workspace path, so one session structurally belongs to at most one workspace. Deleting a Workspace removes only this registry record and account: directories, user files, and session logs remain, and the Sessions become Ungrouped (decision).