📝 Track CI Node-baking work in backlog

Record chore/fix-ci's two done steps and the remaining ops step (build/push
the image; first CI run is the acceptance test). Glyph/tag coupling honoured:
every ✔ line carries @done, open parent stays ☐.

backlog.tasks

@@ -45,3 +45,7 @@ Maintenance:
     ☐ Add a minimal dir-listing webserver to the gitea docker setup for serving landing page (reuse existing reverse proxy)
     ☐ CI writes landing page to a shared volume keyed by project + tag (e.g. `/landing/tiny-pattern-ts/<tag>/`)
     ☐ Browse to `…/tiny-pattern-ts/index.html` in the browser
+☐ Stop Gitea CI re-downloading Node on every job (branch chore/fix-ci)
+    ✔ Share the warm npm cache with the publish job @done
+    ✔ Bake Node into the CI job image (docker/Dockerfile, container.image in ci.yml) @done
+    ☐ Build/push gitea.e1nsnull.de/tmu/act-ci:26.8.2 and confirm setup-node skips the download (first run on the branch = acceptance test) @high