message: fix: breakpoint ts autocompletion
diff: +import type { ITheme } from '../../theme/index';
  +
  export type ResponsiveValue<T> =
  | T
  | null
  | undefined
  | Array<T | null>
  - | { [key in string | number]?: T };
  + | { [key in keyof ITheme['breakpoints']]?: T };
  