we want to yarn install then yarn build then yarn test using the jest

we need to use binary strings so that compressed data is always valid and not corrupted
use explicit binary encoding wherever possible and introduce tests to capture this kind of error or prove that we don't need to worry about it. i have seen it happen in some earlier variations of the types so will have to review them comprehensively at once.

maybe it is more convenient for input parameters so reasonml people can pass in either string or Node.Buffer. if that doesn't work maybe we can make a variant or something to do it.

see bs-fetch example for options examples
to set level, memLevel, and dictionary at least
maybe other zlib options