Make typings for algebras more strict

[Avaq]

This issue assumes the approach in #438 was taken, and proposes a possible follow-up.

Currently, it's allowed to combine Futures with differing rejection types, for example in the following overload for alt, the rejection type is known, but not enforced in the second argument:

Fluture/index.d.ts

Lines 94 to 99 in 06bc7c9

	<L>(second: Rejected<L>): {
	(first: Never): Never
	(first: Rejected<any>): Rejected<L>
	<R>(first: Resolved<R>): Resolved<R>
	<R>(first: Uncertain<any, R>): Uncertain<L, R>
	}

The same goes for the piped version of this type:

Fluture/index.d.ts

Line 91 in 06bc7c9

<F extends AnyFuture, S extends AnyFuture>(second: F extends Rejected<unknown> ? S : never): (first: F) => S

Both could be made to tell the user they are doing something naughty when the user attempts to provide a second Future with a differing rejection type:

<L>(second: Rejected<L>): {
  (first: Never): Never
  (first: Rejected<L>): Rejected<L> // L instead of any
  <R>(first: Resolved<R>): Resolved<R>
  <R>(first: Uncertain<L, R>): Uncertain<L, R> // L instead of any
}

// infer L from F and constrain S
<F extends AnyFuture, S extends AnyFuture>(second: F extends Rejected<infer L> ? S extends Uncertain<L, unknown> ? S : never : never): (first: F) => S

This same principle applies to other algebras that wouldn't normally allow for changes in the rejection branch.