feat(15048): One-sided Type Predicates

[graphemecluster]

Fixes #15048

Why not nominal type (a.k.a. type brand/tag)? It is excessive, and to avoid the trouble people would instead write something like ((v): v is number => Number.isInteger(v))(v) && (() => true)(), given that it just works. It looks bad when hovering over the variables too, especially if there are multiple layers of type guards.
Particularly for the built-in lib, we don't want something like isInteger(number: unknown): number is number & { readonly integer: unique symbol };, so this is the feasible solution.

Ultimately I would also like to implement negative predicate and predicate with non-boolean return value such that an overload for {ReadonlyArray, Array}.some like some<S extends T>(predicate: (value: T, index: number, array: T[]) => !(value is subtypeof S if truthy), thisArg?: any): !(this is subtypeof S[]); could be added to the built-in lib, which addresses #46650 and #47574.

The exact syntax is not confirmed, and is open to discussion.

[typescript-bot]

The TypeScript team hasn't accepted the linked issue #15048. If you can get it accepted, this PR will have a better chance of being reviewed.

[sandersn]

Can you mark this as draft or wait until we agree on a design in #15048 ? There's not much point in the reviewing the code when the semantics are still up in the air.

[graphemecluster]

Definitely will wait for it.

[sandersn]

Unfortunately, we haven't had time to work on the design of one-sided predicates and this PR is quite old now. I think it makes most sense to close this PR and re-open it if something changes.