Remove Unused Leveldown Binaries and Config from Desktop

[bitmold]

In Quiet, leveldown was replaced with a (now pretty outadted) version of classic_level a few years ago.

This PR removes some unsued json+js, as well as unused leveldown binaries for mac + windows + linux , hopefully simplifying some of the confusion around Quiet's leveldb integration.

Am able to run npm run start:desktop and upload images just fine without these.

You'll notice that binaries for iOS and Android still exist on this PR, that's because similar work to get rid of leveldown on mobile is in my mobile PR #3011.

Haven't tested this locally on Windows like i have linux + mac..., but the Windows CI seems fine

[bitmold]

cc @holmesworcester this PR doesn't do anything other than remove unused leveldown DB binaries (that are named very similarly to binaries Quiet actually uses and of course needs to function - the leveldown bins being deleted here were in fact confusingly replaced with classic-level binaries, which sound older because of the classic but actually in fact are the newer ones used by the app.....) --- I spent a nontrivial amount of time trying to make sense of the different leveldown/classic-level binaries when working on #3011. once i realized i eventually needed to rebuild classic-level on android, i wasted time not knowing which binary i'd need to swap out for my modified one, etc.

once this is merged, other devs won't have to waste time trying to wrap their head around which bin is doing what like i did

[bitmold]

Closing, just threw these 2 commits on this forgotten PR onto the related #3092