Annotate the `new Version(...)` call with `/* @__PURE__ */` to signal to optimizers that the constructor is side-effect free.
Without this hint, bundlers such as Terser or ESBuild may conservatively retain the `VERSION` instantiation even when unused. With the annotation, the constant can be tree-shaken away in production builds if not referenced, reducing bundle size.
This PR was merged without API docs and general rollout plan.
We can't release this as is in 5.1 without a plan for documentation, cli integration, etc.