[FEATURE]: Marker interfaces about boa-constrictor

[AutomationPanda]

Okay, so I did some playing around, and I realized why AnswerCache uses IInteraction directly. The answer cache holds answers to any kind of cacheable questions. Its methods control the type conversion, but the internal Dictionary uses the IInteraction type as the key type. I suppose a non-generic Dictionary could be used instead.

[AutomationPanda]

#244 removes IInteraction from AnswerCache so there's one less reference to it.

[AutomationPanda]

That's interesting.

Philosophically, the IInteraction interface is the base interface for all interactions: Tasks and Questions. I like having that shared root.

Pragmatically, IInteraction is used by AnswerCache. I'm not sure why it doesn't use ICacheableQuestion instead. I don't remember. I'll ask the other core contributors.

Rather than removing IInteraction outright, we should consider if there is anything we should add directly to it. I don't think an attribute would be appropriate.