Refactor instanceof

[davidkpiano]

Let's figure out an alternative approach than using instanceof. While it sounds a little bit silly it really can be a PITA and I know that the pain ain't mine only - I've seen Ben Lesh and Jay Phelps mentioning this stuff on Twitter once.

It's just that with complex-enough applications/monorepos it's somewhat easy to end up with multiple copies of a library - and even though the structures created by one of the copy and handed out to the other one should be compatible, they are not if we end up using instanceof. Even though the class itself in each of copy might be 100% the same the runtime can't tell that and will fail on every executableAction instanceof ExecutableAction in each such situation

Originally posted by @Andarist in #2484 (comment)

[davidkpiano]

@Andarist Until it can be demonstrated that this is an actual problem, let's close this one out.