Package support
What version of Box2D does @box2d/core use and is there a migration to Box2D v3.1?
It's based on the 2.4.1 Version, see b2_version in https://github.com/Lusito/box2d.ts/blob/master/packages/core/src/common/b2_common.ts#L138
It's relatively up to date with the latest changes of the 2.x Version (missing some since june last year).
I'm not planning on a 3.x migration any time soon, as 3.x has been rewritten from scratch, and I'd have to do that here too and that would be a lot of work (which I don't have the time for right now) and probably would break the particles package.
Since the box2d/lights package is agnostic to the physics engine, it would probably work with a wasm version of box2d 3.x