Let an app connection record on a shared-host runner (admins only).

Admins only. A shared-host capture runner (a roscoe) is a GPU recorder on a machine that also runs the owner's own work: it records only Sleeper's own takes and the app connections an admin puts on this allow-list, and opens only the app origins its own box config names. Allowing is the admin's call: the server checks only that the connection exists, and logs who allowed it. Allow only Sleeper's own connections and pilots the owner approved. Idempotent (a second call replaces the note). 404 not_found for an unknown connection. Logged. Scope: account:write. Free.