Some gradient interpolations are quite broken

## Description

Certain colour combinations make the gradient go wild. I don't even mean that gradients of end stops of <9 lightness difference fail to generate altogether, but this:

## Steps to reproduce

1. Go to http://leonardocolor.io/
2. Generate a sequential gradient between #054cbe and #8a7401 in the OKLCH colour space.

## Expected behavior

Smooth gradient.

## Screenshots
Some of the other colour interpolations bug out too.

CAM02(Ch):

Lch (only slight banding on the left):

HSL and HSV's circle analysis counts as abstract art :)

## Environment

Win 10, Firefox 145.0.2

Start by reproducing the sequential gradient at leonardocolor.io between #054cbe and #8a7401 in OKLCH, then compare the other reported CAM02(Ch), Lch, HSL, and HSV cases. Trace the gradient interpolation entry point and identify where the generated colors diverge from a smooth gradient; done means the reported combinations render smoothly without breaking or severe banding.

Written by the indexing model from the issue text.