promote a preview page to site root via zip -j, no file moves

For a static site deployed by CI (GitHub Action zipping files and pushing to AWS Amplify), you can stage a redesign at a subpath and later promote it to root without moving or renaming anything. Stage: put the new page at new/index.html; in the deploy step add zip site.zip new/index.html (no -j, preserves path) so it serves at /new/. Promote to root: change the root zip line from index.html to new/index.html WITH -j (zip -j site.zip new/index.html ...) because -j strips the directory and stores the entry as its basename index.html, so Amplify serves the new page at /. The old index.html stays untouched in the repo as an instant rollback (flip the line back). Amplify serves /new/ from new/index.html by default and 301s /new to /new/; verify a promotion by curling the root for a new-only marker string rather than trusting the deploy job status.