fix: Protect Request and Session from partial mutations on request handler failure

[Mantisus]

Description

• Protect Request and Session from partial mutations on request handler failure relevant with AdaptivePlaywrightCrawler

Issues

• Closes: Track changes made to request and session in RequestHandlerResult #1514

[Pijukatel]

I am not sure about doing this due to some race conditions. My concern is reverting the changes made to the session by parallel handlers.

Scenario with 2 handlers running at the same time and both using the same session:

Both handlers create their copy of the session. (Identical at this point)
Both handlers modify the session.
One of the handlers fails and reverts both modifications.

Also, we should keep JS version aligned, so please add a note here if any changes should be made there as well:
apify/crawlee#2798

[Mantisus]

I am not sure about doing this due to some race conditions. My concern is reverting the changes made to the session by parallel handlers.

Yes, I am also concerned about the race condition in the session for some cases. But I am not yet sure about the best approach to avoid it.

One of the handlers fails and reverts both modifications.

This should not revert both modifications.
The failed handler will continue to work with the original session.
The successful handler will apply the update from the copy to the original.

I will try to add a test that reproduces this behavior.