Graph Inspector overlay resizes from the bottom when dragged from the top edge in Graph Toolkit

Steps to reproduce:

1. Create a new project using Universal 3D template
2. Import the attached "MySimpleGraph.cs" script
3. Go to Assets > Create > Graph Toolkit Samples > Simple Graph
4. Open the created graph
5. Observe the opened Graph Inspector overlay
6. Click and drag at the top of the Graph Inspector to resize it downwards
7. Observe the behavior

Actual results: Overlay is resized from the bottom of the window, instead of where it is being dragged from (the top)

Expected results: Overlay is resized from the top where it is being dragged from

Reproducible with versions: 6000.4.1f1, 6000.5.0a9, 6000.6.0a1

Tested on (OS): Windows 11

Notes:

• The resizing behavior feels unnatural. Standard UI practice dictates that the edge being dragged is the one that moves, while the opposite edge remains anchored, current behavior is counter-intuitive