Initialize Tapioca

[vidusheeamoli]

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Tapioca is a library used to generate RBI (Ruby interface) files for use with Sorbet.

[issyl0]

Looks good to me! Would be good to put in the commit message what benefits this gem will give us in relation to Sorbet. The "203 errors => 29 errors" that you explained in Slack, for example.

[issyl0]

I'm going to assume that there's more to be added to this PR - like the RBI files that Tapioca generates for the gems - and not merge this tonight. 😇

[issyl0]

It's a lot of changes, but Tapioca fixes the vast majority of problems and means that we don't have to handcraft our own RBI files for gems (we just have to run bundle exec tapioca sync every so often), so that's good. (They also must be committed to the repo, before anyone asks that question.) Thanks, @vidusheeamoli!