Introduces AsyncPlugin to serve as a standalone library-plugin entry point for the Async library. This allows other plugins to depend on Async without bundling it directly. The plugin installs a disconnect hook on start and ensures proper shutdown of tracked scopes.
Bundles core + ecs + binding into a single shaded JAR via
com.gradleup.shadow. Regular jar stays enabled so composite builds
in examples/ can consume project(":dist") directly.
kayjaydee