R1:4eadcf975ade

Implement most Differential actions against ApplicationTransactions

Summary: Ref T2222. Implements the simpler actions (abandon, reclaim, close, reopen, plan changes, request review) in a transactional way with validation and effect checks.

Test Plan:
- Rigged submissions to point at the Pro controller.
- Rigged dropdown to have all these options all the time.
- Tried to apply about 20-30 of these operations to various revisions and always got the expected result (success, error, or no-op).