colorjs uses internal short names (p3, a98rgb, prophoto) that don't
match the CSS predefined color space identifiers required by the spec:
- p3 → display-p3
- a98rgb → a98-rgb
- prophoto → prophoto-rgb
This caused toValue() to emit invalid CSS like `color(p3 ...)`, which
the css-tree lexer rejects when re-validating the value in the CSS value
input (e.g. after a round-trip through the style panel).