bump: minor
type: feat
Package-declarable namespaces & engine systems (#62) — the two hooks that made `Foo.*` stdlib namespaces and engine-owned systems compiler-hardcoded are now data-driven registries, so a package registers them with no compiler edit. `@Namespace(Name)` on a function opens a `Name.method(…)` namespace that dispatches to the bare `name_method` through the same generic path the built-in namespaces use (applied only after them, so it never shadows a core one). `@EngineSystem(Component, Phase)` registers an engine-owned system the frame loop runs each phase when the component is present — the package-declarable form of the built-in SpriteAnim/Motion/Light2D systems, reading components by name through the reflection ABI so an unused registration is byte-identical. Both annotations are keyword-free. The core stdlib keeps its optimized codegen (byte-identical output; the C-free bootstrap fixpoint is untouched) and packages ride the generic registry alongside it. This completes the packaging prerequisite for shipping gameplay-controller libraries (#58–#61) as real packages. See docs/PACKAGES.md.