fix(website): restore the download status element and the notarization gate

"nit: remove terrible ui warning" deleted two things, and only one of them was
a UI nit.

`#portal-release-status` is not decoration: `updatePortalDownload()` in
dither.js bails at `if (!button || !note || !os || !arch) return;`. With the
span gone the function returned before touching the button, so the download was
frozen at "no macos arm64 build yet" forever -- including after v0.1.0 is
promoted and portal-release.json flips to available. The button would never
have gone live.

`verify-website.sh` also requires the literal "portal is not notarized by
apple", which is why every deploy from main has failed since that commit. The
gate exists because macOS blocks the first launch of an ad-hoc signed build and
the site is supposed to say so rather than let it surprise people.

Both restored on the one existing release-note line, as a single inline clause
instead of the three-clause paragraph that was there before, so the disclosure
is present without the wall of text.

commit

9255f35cb597fc49977b184f7246c353cc5e0e57

parent

0d391ba757e8fbef9e1bb829482ce4ceca2d9b6f

author

Dami <dami.etoile@gmail.com>