GAME now accepts a space-separated list and defaults to 'all', building and
attaching every game's zip to a single release instead of one game per tag -
which matches the repo being a collection. Release body is the game's own
README for a single game, or the collection README for several.
Asset upload replaces same-named assets, so re-running is idempotent.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>