There is no definitive requirement for a rigidbody on an Interactable but the previous changes that prepared rigidbody for kinematic changes has meant that a Rigidbody is required to set up the state to prepare for any kinematic change.
This fix just makes sure these state preparations are only done if a rigidbody is provided, so it no longer needs a rigidbody if not required.
There is no definitive requirement for a rigidbody on an Interactable but the previous changes that prepared rigidbody for kinematic changes has meant that a Rigidbody is required to set up the state to prepare for any kinematic change.
This fix just makes sure these state preparations are only done if a rigidbody is provided, so it no longer needs a rigidbody if not required.