Fix Child Process not working for BGREWRITEAOF on MacOS + Logging Improvements

[KaviiSuri]

This PR fixes BGREWRITEAOF failing completely, Specifically for MacOS for now .

The root cause is that macos doesn't set pid to 0 for child process

The solution is to record get original pid of main process and do isChild := syscall.Getppid() == originalPID. The pid == 0 check is unreliable and breaks on maocs m2 in my testing.

This PR also adds logging features and a bit of refactoring to reuse code and allow for logger.With(...attrs) to be logged correctly

[KaviiSuri]

@lucifercr07 @vinitparekh17 could you review the changes here?

[JyotinderSingh]

Please rebase on the latest master

[KaviiSuri]

@JyotinderSingh , done

[KaviiSuri]

@JyotinderSingh are there any blockers to merge this? Any effort required from my end?

[JyotinderSingh]

@JyotinderSingh are there any blockers to merge this? Any effort required from my end?

Reviewing this

[lucifercr07]

Thanks @KaviiSuri for fixing this, validated locally works fine in single threaded mode.
Can you please point to doc where you found this Macos M2 behaviour, wasn't able to find any concrete documentation around this behaviour.

[KaviiSuri]

@lucifercr07 i couldn't find the exact docs, but i did find a lot of people facing the same issue. Although, the solution implemented is quite generic, we just compare pid with previously recorded one, so it should be safe regadless if the fork return value behaviour

also, apparently, both implementations of golang and python had to deal with such peculiarities on MacOS

[JyotinderSingh]

Thank you for these fixes.