R1:fbfe73045214

Support more transactions types in RepositoryEditEngine

Summary:
Ref T10748. This supports more transaction types in the modern editor and improves validation so Conduit benefits.

You can technically create repositories via `diffusion.repository.edit` now, although they aren't very useful.

Test Plan:
- Used `diffusion.repository.edit` to create and edit repositories.
- Used `/editpro/` to edit repositories.

Reviewers: chad

Reviewed By: chad

Maniphest Tasks: T10748

Differential Revision: https…