For upcoming feature work, we want the ability to make a single request to publish a bunch of individual items (review requests and reviews) all together. To do this, we're introducing a new API-like endpoint for performing batch operations. This doesn't exist in the official API because it doesn't really mesh well with REST, and the actual endpoint may be in flux for a bit. We already have some batch-like operations in the dashboard UI that currently just make a whole bunch of API requests for closing review requests or changing visibility state. This new endpoint will also enable these workflows, so we can handle it much more efficiently. This is work-in-progress change that does most of what I have planned. There are two major pieces left to do: 1. Handle the partial-publish case where we get some errors. I've not yet decided whether to proceed with what we can and return a "mixed" status with errors, or refactor the publish path inside ReviewRequestDraft to allow us to do all prep and validation before actually publishing anything. 2. Create the new bulk e-mail. Unit tests exist for most of the functionality but I'll be expanding those too. Testing Done: Ran new unit tests.