The cordis preset moved `bash-env`, the `subagents` registry, and its
spawn/fork backends into entry-local realms. A host row that injects a service
is the criterion for host-plane ownership: `apps/cli/src/web.ts` injects
`bash-env`, and `dsh-host-apiproxy` injects `subagents` to answer the
browser's cross-session queries, so both waited forever for a service only
sessions provided. A provider name also registers once, so the second session
would have collided regardless.
This layer introduces the preset, so it is where the plane belongs — a later
layer already corrected it, which left this layer and the docs one unmountable
on their own. The composition test stops disabling `api-gateway` with it: the
row whose pending injection names the break cannot be the row the test turns
off, so the boot audit now covers the whole host-plane injection graph.