Moving an object linked to a stair can prevent all stairs from being moved

Description:
After moving an object that is linked to a stair, Cygon can enter an invalid state where no stairs can be moved anymore.

The issue persists until another action is performed, which resets the editor state and restores normal behavior.

Steps to reproduce:

1. Create a stair linked to another object

2. Move the linked object

3. Try to move any stair

Actual behavior:
No stairs can be moved after the linked object has been moved. The editor remains in this state until another action is performed.

Expected behavior:
Moving an object linked to a stair should not affect stair manipulation. All stairs should remain movable immediately after the operation.