Adds web-overrides/popup-designs/ with the 4-up preview (preview.html) and
three standalone candidate designs (a-strip.html / b-terminal.html /
c-minimal.html) so we can revisit the alternates later without re-running
the design generator. Owner picked A.
Design A is wired into Jellyfin's stock .upNextDialog by overriding its
CSS to a full-bleed bottom 26 % strip with white 'Start Now' CTA and a
custom SVG countdown ring that mirrors .upNextDialog-countdownText. The
DOM stays intact so Jellyfin's own countdown timer and click handlers on
.btnStartNow / .btnHide keep working untouched.
Shim is bracketed by NEXT-EP-POPUP-BEGIN / NEXT-EP-POPUP-END markers
inside the existing ARRFLIX-SHIM block in web-overrides/index-dev.html.
Only deployed to dev (dev.arrflix.s8n.ru) for spot-check; promote to
prod once verified by editing prod's index.html the same way and
redeploying via the nsenter trick.
Adds bin/revert-next-ep-popup.sh — sed-deletes between markers, defaults
to dev with --prod flag for prod target. Saves a timestamped backup and
prints the redeploy command.
