API improvements

[NateBaldwinDesign]

Description

Refine the API props and options for Leonardo to be more intuitive and consistent.

Considering there are other tools out there (including the d3 and chroma.js libraries) that have similar options, conforming to similar prop names or casing styles would make this tool more intuitive for consumers who are familiar with those tools.

For example:

• Lower case colorspace names: 'lch' instead of 'LCH'
• colorspace prop should either be camel case, or use a more literal term like interpolate/mode
• output may be better surfaced as format (eg, d3 formatRgb)

Overall evaluation and comparison of prop names and values should be done beyond those examples.

Why do you need this feature?

Solidify the API for Leonardo by relating to existing language, props, and values expressed in other similar tools or industry standards.

Leonardo package and version

Additional context