FX.131 Add-ons publish with the release: one command, held until the apps carry what they need

Owner 2026-11-08: add-ons that are ready must not wait for someone to remember them. bin/addon-package.php --release=0.9 checks every add-on against the add-on API 1.4 the 0.9 apps report and publishes it only when every app it targets has 0.9 (or newer) as current AND that build holds every engine:/host: file the package imports; until then it is listed as HELD with the reason (pid, lighting and harness are held now: CadCraft current is 0.8.2). After the release moves current: sudo -u www-data php bin/addon-package.php --release=0.9 --apply. Also: add-on help compiles per language (help/help.<locale>.js, build-help.php --addon) and the add-on loader picks the page's language (hvac and piping 0.9.0, 11 languages, machine drafts). Run sheet: docs/0.9-sessions/first-builds-09.md § Add-ons at release.