Fix the sun in L_World and L_Gym: positional unreal.Rotator is (roll, pitch, yaw)

Both scripts passed (pitch, yaw, roll) and pitched the sun upward, so every scene rendered as night and the
viewport's auto exposure sat at EV -8.5, which is what the 'cached lighting is going to be clipped' warning
reports. Keyword arguments now; the gym script re-applies the rotation on an existing sun; the world script
removes the old external actor folder on disk rather than through the asset library, which cannot load
streaming proxies on their own.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

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Content/Maps/L_World.umap

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