Add SulfurCubeSwallowEvent

[kacimiamine]

Add a new event to the sulfur cube swallowing an item after the player interaction.

[Strokkur424]

I generally like the QoL this event provides. For anyone following along, with PlayerInteractAtEntityEvent, replacing the cube's contained item on interact can be done like so:

@EventHandler
void onInteractWithSulfurCube(PlayerInteractAtEntityEvent event) {
    if (!(event.getRightClicked() instanceof SulfurCube cube)) {
        return;
    }

    ItemStack is = event.getPlayer().getInventory().getItemInMainHand();
    if (is.getType().asItemType() == ItemType.SHEARS) {
        return;
    }

    if (!cube.getEquipment().getItem(EquipmentSlot.BODY).isEmpty()) {
        return;
    }

    event.setCancelled(true);
    cube.getEquipment().setItem(EquipmentSlot.BODY, ItemType.BIRCH_LOG.createItemStack());
    event.getPlayer().swingMainHand();
}

With this new event, that is simplified to just this:

@EventHandler
void onSulfurCubeSwallowItem(SulfurCubeSwallowItemEvent event) {
    event.setNewItem(ItemType.BIRCH_LOG.createItemStack());
}

Generally, a lot of entity interaction stuff is left just as a generic PlayerInteractAtEntityEvent. But in this case I'd argue there are enough lines saved and logical edge-cases (like that top version does not handle the small sulfur cubes not being allowed to swallow items normally) for this event to make sense.

The way it is integrated with NMS code also makes complete sense, for this reason I approve.

[kacimiamine]

The punctuation and comments should be all resolved now