update-package.sh no longer builds anything or publishes GitHub release
assets: every package now tracks an upstream deliverable, so the only work
left on a new version is pkgver + checksums. BUILD_DEPS survives for the
CI test build of packages that compile in the PKGBUILD.
Removes the seven packages that cannot be made compliant: upstream ships no
Linux binary to point at, and a maintained source package for each already
exists in the AUR, so a rebuilt version would just be a duplicate.
gearlever-bin, gnome-network-displays-bin, librepods-bin, planify-bin,
protonplus-bin, thonny-bin, trayscale-bin
README documents the rule and why, so the pattern does not come back.