Add the playbook that deploys one Site

The playbook pulls the tag from the registry, creates the data root owned by the
app user, runs the container with its config baked into the image, waits for
health, then verifies the data directory as the app user so a permissions
mistake surfaces at deploy time. Caddy is pointed at the app with a stable
marker, so a temporary hostname can be checked beside the live site and the
cutover is one invocation with the retire flags set.

README.md

@@ -6,11 +6,21 @@ photographed Pages, replacing the `scp`-a-JPG workflow. One instance per Site;
 
 ## Status
 
-Built: Site config, the Menu Set store, the image pipeline, the
-customer-facing renderer (landing page, Section pages, archived sets, media
-route) with the approved design, and the admin (sign in, create a set, upload
-and reorder Pages, preview, publish, restore, delete). Not yet built: the
-container, the Ansible playbook and the deploy.
+Built: Site config, the Menu Set store, the image pipeline, the customer-facing
+renderer (landing page, Section pages, archived sets, media route) with the
+approved design, the admin (sign in, create a set, upload and reorder Pages,
+preview, publish, restore, delete), the `verify`/`repair` CLI, the container and
+the Ansible playbook. Not yet done: the parallel-run deployment on `monoco`,
+which needs a human present.
+
+## Deploying
+
+```sh
+./deploy.sh 2026-09-22          # tests, build, push to registry.tanshu.com
+```
+
+then the playbook in `ansible-playbooks/menu-admin/` — its readme covers the
+parallel run, the `site.env` step that gives the admin a password, and cutover.
 
 ## Layout