Support aborting async tasks via `AbortSignal`

[ShaMan123]

Description 📝

I want to be able to abort async work that is no longer needed (superseded or aborted altogether):

• a model loading
• an outliner being repeatedly updated
• an ifc coversion that has been dropped

Related: ThatOpen/engine_fragment#173 (though it doesn't actually provide an AbortSignal functionality).

Suggested solution 💡

Every async method should accept an { signal: AbortSignal } providing the consumer full control over aborting it.
IMO it should a design rule enforced by lint.
It is the only way to bridge the threaded/async nature of the packages.
I have spent a lot of time and effort trying to workaround this with queues etc. - it is awkward and error prone.

Alternative ⛕

NONE.
Currently each task is drained and the consumer must reconcile the results when it settles.
This is extremely suboptimal, e.g. #802

Additional context ☝️

ThatOpen/engine_fragment#305

Validations ✅

• Read the docs.
• Check that there isn't already an issue that requests the same feature to avoid creating a duplicate.