Creates bone followers based on the current entity model.

Bone followers are Entities whose Physics Object follows a specific bone on another Entity's model.
This is what is used by prop_dynamic for things like big combine doors for vehicles with multiple physics objects which follow the visual mesh of the door when it animates.

Be mindful that bone followers create a separate entity (phys_bone_follower) for each physics object.

You must call Entity:UpdateBoneFollowers every tick for bone followers to update their positions.