ci: automated release workflow (install + update packages)

[sanmaxdev]

What

Adds a Release GitHub Actions workflow that triggers when a v* tag is pushed, builds the distributable packages, and publishes a GitHub Release with auto-generated notes. This replaces the old local PowerShell packaging scripts with a reproducible, CI-built release.

Artifacts produced per tag

Artifact	Purpose
linkforge-v<version>.zip	Full, self-hostable install package — bundles production vendor/ and compiled public/build, with dev-only files (tests, CI, JS build configs) stripped. Files sit at the archive root for extract-into-webroot installs.
linkforge-update-v<version>.zip	Incremental package for the in-app updater (Admin → Updates). Contains only files changed since the previous tag, laid out as update.json + files/… exactly as App\Services\Update\Updater expects.

How it works

• .github/workflows/release.yml — sets up PHP 8.2 + Node 20, runs composer install --no-dev + npm ci && npm run build, then calls the two build scripts and publishes via softprops/action-gh-release.
• .github/scripts/build-install-zip.sh — git archive of tracked files + production vendor/ + built assets, minus dev tooling.
• .github/scripts/build-update-zip.sh — diffs the previous tag to collect only changed runtime files, generates the update.json manifest, bundles rebuilt assets when front-end sources changed.

Release process (also documented in CONTRIBUTING.md)

1. Bump config/linkforge.php version via a PR.
2. git tag v1.1.0 && git push origin v1.1.0.
3. The workflow builds both zips and publishes the release.

Notes

• update.json layout verified against Updater::inspect() / apply() (version-must-exceed-current is enforced there).
• No application code changed; CI (tests / lint / assets) should pass unaffected.