MSW Packages — Official Prebuilt Catalog is the official MSW first-party repository of prebuilt feature packages. Before writing any standard game feature from scratch, check this catalog first — if a package matches, propose integration instead of zero-from-scratch implementation. This skill is a thin index. Per-package details (README, source, integration steps) are fetched on demand from GitHub rather than mirrored here, so the catalog stays current automatically. --- Decision Flow Default posture : ask the user before integrating. Do not auto-install without confirmation — packages can co…