add `TurnOwner` helper method to `Engine`

[RyanOld]

In the case of seele A6, it is neccessary to add a condition that if :

• current turn is seele's, and
• she's on her resurgence turn

That the advance forward be delayed to the TurnEnd.
In order to make this comparison, we need to add engine access to who the current turn belongs to.
Might want to resolve this issue along with #187 as both problems seem similar.