[Suggestion] Use SparseSets for ActionState Component and Benchmarks

[chrisburnor]

Bevy 0.5 introduced SparseSet Storage (see Release Notes) for components with high add/remove volume to avoid . If I'm understanding, from my (somewhat cursory) reading of the code that ActionState probably falls into this category and would probably generate a performance boost if added.

I might be very wrong on the way that ActionState is implemented, but it would be very good to add some benchmarks for performance validation.

[zkat]

maybe? I'd take a PR for this :)

[chrisburnor]

I'll, see what I can do, though likely the higher priority for me would be #28. If I can figure out the internals enough for that one, I should have enough to implement this one too.