feat: run augurs computation in worker thread

[sd2k]

This is mostly a PoC PR demonstrating how we might do this, in case it comes up in future. I've used workerize-loader to simplify the creation of the worker but we could probably do it by hand to avoid the dependency if we wanted.

Edit: actually I just profiled this and it results in a considerable amount less jank for the 'most relevant' sorting. Here are two profiles where I switch to the Most Relevant sorting, before and after this change; note that in the second one, all of the expensive work is run in the DOM worker, and there's a lot less jank reported.

I think this needs a bunch of double-checking before merging because I may have missed something (e.g. does changing the publicPath to be absolute matter? ).

[matyax]

Thank you Ben! We'll be looking at it soon.