Whether an aborted signal was aborted by a timeout rather than by its caller. Decided by the
reason's type: a TimeoutError (what AbortSignal.timeout() raises) or a reason flagged
TimeoutAbortReason. The words of a reason never decide it: a caller is free to abort with
"it timed out on my side", and that is still the caller cancelling.
Whether an aborted signal was aborted by a timeout rather than by its caller. Decided by the reason's type: a
TimeoutError(whatAbortSignal.timeout()raises) or a reason flagged TimeoutAbortReason. The words of a reason never decide it: a caller is free to abort with "it timed out on my side", and that is still the caller cancelling.