implement on-death of unit effects

[lijim]

We'll need #255 to implement this. Units can go to the cemetery on other players' turns, meaning we need to allow players to resolve their effects

• To implement implement effect-resolution of opponents' effects on their turns #255, we will need to move the effectQueue logic into the Board object, up a level from Player.

• On the code in applyGameAction for returning early if a game action is taken by a non-active player, we'll need to add an addition check for if the player is the active one for resolving the effect (not just whoever has the current turn):

// Error out when event is being emitted by the non-active player
    if (activePlayer?.name !== playerName) {
        return board; // TODO: implement error UI
    }

• Lastly, we'll need modify getLastEffectForActivePlayer and add a corresponding test in GameDisplay to test that the game properly displays the "Resolving: " text for a player resolving effects that is not the active player