* Gradient picker
* Fix up color picker layout CSS problems
* Begin hooking up SpectrumInput for gradient in the ColorPicker
* Working gradient picking on the frontend only
* Plumb FillColorChoice into the backend
* Hook everything else up, just with a weird bug remaining
* Fix some svelty reactivity issues
* Add and remove stops
* Cleanup
* Rename type
* Fill node document format upgrading
* Fix lint
* Polish the color picker UX and fix a bug
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Co-authored-by: 0hypercube <0hypercube@gmail.com>
Keavon Chambers