Parametric theme creation interface

[vkottler]

Continue progress made on https://github.com/vkottler/svgen/pull/42.

Also upgrade the theme viewer to see the rgb and hsla constructors like https://hslpicker.com/ does.

Possible parameters:

• sweep saturation/lightness (would be interesting to see 2 distinct themes with these sweeps)
• linearity / polynomial fits for N points?

[vkottler]

https://developer.mozilla.org/en-US/docs/Web/CSS/color_value/hsl

https://developer.mozilla.org/en-US/docs/Web/SVG/Element/text

[vkottler]

use-case for hsla/rgba constructor showing - why are the text colors saturated?

[vkottler]

Workflow upgrades: host SVGs + open browser tab, automatically re-render on changes to tasks sub-directory.

Eventually auto-refresh would be nice, wonder if the browser knows how to do that?