Update node version of sub-packages

[jjspace]

Our primary cesium package requires node >=18.18.0 but the subpackges engine and widgets still only require node >=14.0.0. I would expect these to match.

Technically Node LTS is up to 18.20.4 so maybe we want to update all 3 but I'm not sure it's worth doing that and forcing everyone downstream to update node in case they have some external requirement. As long as they're on v18 I think that's good for now