Feature request: Add more onErrorXXX stream operators

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Motivation:
As a daily Java developer , I think the onError* operators are very easy to use, that may not apply to Scaladsl.

eg: spring-projects/spring-framework#31352
refs:reactor/reactor-core#535
refs: #24992

Currently:

Reactor-core	Pekko	Suggestion
onErrorResume	recoverWith
onErrorComplete	onErrorComplete ( added )
onErrorReturn	recover/recoverWith
onErrorContinue	withAttributes(...)
onErrorStop	withAttributes/defaultBehavior
onErrorMap	mapError

Prons: Easy to use , especially for Java developers.
Cons: More overhead.

And things to notes are:

1. Even reactor-core think the onErrorContinue is another one billion of mistake, but that will not apply to Akka stream, because the attributes will not leak to all the chains up.
2. As the Akka stream support add supervision strategy to the final RunnableGraph, not sure if we need add some of these method to the Graph too.