2026-08-20 — Website docs unversioned (default)

Set Antora version: ~ for the website component so the UI shows default, not master (git branch is not a docs version).

Matches onboarding/infra; page URLs stay under /website/… (no /master/ segment).

Hub playbook keeps @antora-supplemental/unversioned-component-urls so bare /component/ URLs for numbered components are version choosers.