Add Sylvan Labyrinth win condition

[mysterymagination]

• Treant needs to avoid lava pit by default
• When the wooden egg is seized and placed in the lava, treant will walk into the lava and take damage
• Only damage from the lava pit will kill the treant permanently, but it will flee the lava as soon as it recovers the wood egg. Player needs to place the egg in the lava so that the treant has to spend as much time in the lava as possible and/or damage the treant close to death before leading it in. The lore should include hints that this is the vector to victory!

[mysterymagination]

~todo~: we got the wood egg death event in, but what to have the treant do? The original idea was to have him jump in the lava after the egg and die; this only makes sense if he wouldn't enter the lava previously. I looked at blocking volumes, but it seems a greenlist with just player for collision is tough, as is a redlist of just the treant; it wants to do lump everything in by collision profiles and I don't want to change the player collision profile from Pawn because that's scary. Instead, simply removing the lava pool from navmesh volume might be better and then at egg death we can have special behavior that moves the treant into the pool. Hopefully not having a navmesh won't be a problem if I give a direct movement command? or we could add that area to navmesh dynaically.

• I added a nav mod volume to block off the lava pool by default; when the egg dies, we can just find it, remove it, and then direct the treant to move to the last location of the egg. Boom, done... as long as the navmesh recomputes itself at runtime when the nav mod volume is removed.

[mysterymagination]

~todo~: make the egg not liftable until you have all the treasures

[mysterymagination]

~todo~: make it possible to launch the wood egg from a grab, and enable its physics so we can huck it into the lava instead of walking it in

[mysterymagination]

~todo~: apparently the teleport near player BT task does not care about blocker navmod volumes; the treant can teleport into the lava pool right away without the egg being involved at all. EDIT: I added logic to check teleport location inside the bounding box of the lava block volume