Monadic versions of scanLeftNe* and scanRightNe* functions

[satorg]

Copied from the Discord channel.

I'm thinking whether it makes sense to add monadic versions of scanLeftNe* and scanRightNe* functions similar to groupByNe*A (which would complement regular groupByNe*)? For example, for scanLeftNeSeq there could be

  def scanLeftNeSeqM[F[_], B](b: B)(f: (B, A) => F[B])(implicit F: Monad[F]): F[NonEmptySeq[B]] = {
    val nesTraversable = Traverse[NonEmptySeq]
    nesTraversable.sequence(scanLeftNeSeq(F.pure(b)) { (fb, a) =>
      F.flatMap(fb) { f(_, a) }
    })
  }

It is -M because I didn't manage to come up with how to avoid flat-mapping in the inner f therefore F[_] has to be a Monad instead of just Applicative.