Add `scaleFactor` options

[ianjennings]

Mac file sizes are super large due to retina display.

@alexpelan wrote an implementation of scaleFactor for the Swift binary here:
wulkano/Aperture#73

These options will need to make it into index.ts on merge:
https://github.com/wulkano/aperture-node/blob/main/index.js#L42

I'm not familiar with Swift, so I'm having trouble building the binary. Tonight I was able to produce x86_64-apple-macosx/release/Aperture though this doesn't fit the script found in package.json so I'm hesitant to move forward here.

Happy to add the Javascript options if someone can provide the binary.

[chrisspiegl]

This wold be great to see this added.

I am not sure what is missing here, this PR #20 mentions that it's already implemented but looks like the Node.js stuff is missing? Is this correct?

[chrisspiegl]

Found a workaround for this issue by using BetterDummy and Virtual Display Monitors in macOS for my Screen Recording needs.

It's not perfect (and needs some setup time if you want to use on your internal display), but it does the job perfectly for me.

My Virtual Screen is setup to be a 1920x1080 HiDPI screen which is a resolution macOS does not really like (or offers) with the internal displays. But this way, I get a 4k image recorded which is a perfect 16x9 that I can include in my video work without it being overly huge on the viewers screen.