window: Move Vulkan check to Controller
Continuation of series of commits to separate the UI and business logic.
Vulkan checking is a non-ui task, thus the process is moved into the Controller and only a callback is added for when the check fails.
I tested via a hard-coded error and found the application fails successfully, but I would like to see a natural successful failure.
Waiting on !39 (merged) to complete first.
Edited by Clocks