Add typings

[willium]

I started off some typings, would love to see this updated and typed :)

declare module "d3-hsluv" {
	import type { ColorSpaceObject, ColorCommonInstance } from "@d3-color"

	/**
	 * Parses the specified CSS Color Module Level 3 specifier string, returning an RGB color.
	 * If the specifier was not valid, null is returned.
	 * See: http://www.w3.org/TR/css3-color/#colorunits
	 *
	 * @param cssColorSpecifier A CSS Color Module Level 3 specifier string.
	 */
	export function hsluv(cssColorSpecifier: string): RGBColor

	/**
	 * Converts the provided color instance and returns an RGB color. The color instance is converted to the RGB color space using color.rgb.
	 * Note that unlike color.rgb this method always returns a new instance, even if color is already an RGB color.
	 *
	 * @param color A permissible color space instance.
	 */
	export function hsluv(color: ColorSpaceObject | ColorCommonInstance): RGBColor

	/** l, u, v, and optional opacity channels */
	export function hsluv(l: number, u: number, v: number, opacity?: number): void

	/** returns an HSLuv color space interpolator between the two colors a and b */
	export function interpolateHsluv(color1: string, color2: string): void

	/**
	 * Returns an HSLuv color space interpolator between the two colors a and b,
	 * but does not use the shortest path between hues.
	 */
	export function interpolateHsluvLong(color1: string, color2: string): void
}