Make union a type that allows destructuring assignment

UnionDestructurable.ts

/**
 * Make union a type that allows destructuring assignment
 * @example
 * ```
 * const props: { a: number } | { b: string } = ...
 * const { a, b } = props as UnionDestructurable<typeof props>
 * ```
 */
type UnionDestructurable<
  Union,
  UncommonKeys extends string = Exclude<
    Union extends infer T ? keyof T : never,
    keyof Union
  >
> = Union &
  (Union extends infer T
    ? { [K in UncommonKeys]?: K extends keyof T ? T[K] : never }
    : never);