It had sequential async calls with complexity O(n), with a variety of redundant
calls. There was also a constant of... 4? 5? for each item. Now, the total
sequence depth is just 3-4.
Completes the `Executed` enum in the router. Adds an `Escape` struct. Both are
needed for testing purposes.
Documents the gas constants in intent and reasoning.
Adds modernized tests around key rotation and the escape hatch.
Also updates the rest of the codebase which had accumulated errors.
