R1:b4af57ec51e1

Rough cut of DrydockRepositoryOperation

Summary:
Ref T182. This doesn't do anything interesting yet and is mostly scaffolding, but here's roughly the workflow. From previous revision, you can configure "Repository Automation" for a repository:

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If it's configured, a new "Land Revision" button shows up:

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Once you click it you get a big warning dialog that it won't work, and then this shows up at the top of the revision (completely temporary/placeholder UI, some day a nice progress bar…