refactor: remove "variants" as a separate subpackage.

Author: Ohh-889

packages/color/src/generate.ts

@@ -1,4 +1,5 @@
 import { colord } from 'colord';
+
 import type { ColorPalette, ColorPaletteNumber } from './types';
 
 const CMY_HUES = [180, 300, 60];