Major, try to keep sync/async at the type level

[mikearnaldi]

Ideally we can use a Kind4 instead of 3 keeping "a" | "s" as the effect type and combine accordingly, unsure if possible in all cases with correct inference.

[mikearnaldi]

WIP #180

[mikearnaldi]

Keeping "a" | "s" is a mess type wise. I have found a better encoding placing:

type ASYNC = unknown
type SYNC = never

Such that: ASYNC | SYNC = ASYNC

[mikearnaldi]

This is released, to be considered still a work in progress, especially in the sense that Stream, Managed & other apis might benefit from the same kind of refinement.

Probably the end goal is to have an eff package containing all the api in this form with a mapping to effect

[mikearnaldi]

#195 Hit a wall on the current design

[mikearnaldi]

done in #199