Use Sinebow for HSB color picker

[micycle1]

The "sinebow" gives a more linear (better) hue cycle vs the naive HSB-based “angry” rainbow.

See https://observablehq.com/@mbostock/sinebow https://observablehq.com/@jobleonard/linear-sinebow

[wrightwriter]

any reason to use that over okhsv/okhsl?

[micycle1]

okhsv would be even better I suppose (a little more complicated though).

[wrightwriter]

It's a couple of multiplies and divisions, everyone copies the code anyways :) Should be trivial to add and lerp in.

[wrightwriter]

There's also the separate issue of lerping linearly between points in the picker... I think it's fine, but you could fit a curve.

[KrabCode]

I'm open to approving pull requests on this but I don't understand it enough to make an effort myself here