ci(chore[docs-preview]): temporarily deploy autodoc-improvements to live docs

why: The autodoc-improvements branch (PR #18) is a large-scale
refactor of the docs surface — new architecture.md, whats-new.md,
gallery.md pages; renamed package pages; a reworked CSS namespace.
Reviewers need to see the rendered output on the canonical domain
before the branch merges, so route pushes on this branch through
the existing S3 + CloudFront + Cloudflare pipeline.
what:
- Add `autodoc-improvements` to the docs.yml push trigger so every
  push on the branch runs the same publish pipeline main already
  uses (S3 sync --delete, CloudFront invalidation, Cloudflare
  purge).
- Mark the added line with a TEMPORARY comment that references
  PR #18 and requests a revert before the PR closes, so the
  preview deploy cannot be forgotten in tree.
- No other workflow change; main still publishes as before.

Author: tony

.github/workflows/docs.yml

@@ -4,6 +4,9 @@ on:
   push:
     branches:
       - main
+      # TEMPORARY: preview-deploy autodoc-improvements to the live docs site.
+      # Revert this line (and only this line) before closing PR #18.
+      - autodoc-improvements
 
 permissions:
   contents: read