Selections API

[dvdkouril]

Would like to allow selecting subparts of chromatin models. The interface could looks something like this:

import chromospyce as chs
url = "https://pub-5c3f8ce35c924114a178c6e929fc3ac7.r2.dev/Tan-2018_GSM3271347_gm12878_01.arrow"
model = load_remote_model(url)
d = chs.select(model, "chr1:10000-20000") # => Arrow bytes

w = chs.Widget(structure=d)
w # => displays the widget with a subset of the data

There is a very simple implementation of selections in chromospace (chromospace.get()) but after some initial tests, it might actually be much better to use duckdb and do the data filtering on the python side.