use bare "three" imports

[ChristopherChudzicki]

I was working on unconed/mathbox#49 and realized we should do the same for this library

What does this do

Previously we were importing from specific three/src files. Now we just import from "three".

Why change? Because:
1. we can still tree shake
2. we were actually (indirectly) using bare imports before, too. E.g., ThreeStrap imports from "three/examples/jsm/controls/OrbitControls", and OrbitControls imports bare "three"
3. "three" seems like the more official import pattern; it's what is documented at https://threejs.org/docs/#manual/en/introduction/Installation

Related

See also unconed/mathbox#49

Some numbers

I was not expecting this to affect bundle sizes very significantly, but it actually did reduce the bundle size pretty significantly, at least for webpack, I think because of (2) above: previously we were including three/src directly, and three/build indirectly (via imports like three/examples/jsm/controls/OrbitControls).

I published a version of threestrap on npm that includes this change, v0.5.1-rc1 and testing with https://github.com/ChristopherChudzicki/bundling-tests:

            0.5.0   0.5.1-rc
webpack     859K    439K
vite        441K    419K

So, that's cool.

[ChristopherChudzicki]

@sritchie I'm working on PRs for unconed/mathbox#49, but realized we should do this also, and would like do update to 0.5.1 as part of the PRs toward unconed/mathbox#49.

[sritchie]

The smaller bundle size is the absolute clincher. Thanks for going the extra mile and doing those bundle size tests...