IndexOutOfRangeException thrown when UI elements are dropped in non-name columns of the hierarchy (active, layer, tag, etc.)

Steps to reproduce:

1. Create and open a new project
2. Create an "Assets/Create/UI Toolkit/Standard Elements/Button"
3. Create the UXML
4. Duplicate it
5. Open the document in the in-scene UI Viewport
6. Right-click the "Name" column header in the Hierarchy and enable every option
7. Grab one of the buttons and drag it under the 'Active' column between the buttons
8. Observe the Console

Actual results: "IndexOutOfRangeException: index -1 is out of range [0, 7]" is thrown

Expected results: Nothing is thrown; the element is placed in the new place (or doesn't if moved far enough)

Reproducible with versions: 6000.6.0b8, 6000.7.0a4

Can’t test with versions: 6000.0.81f1, 6000.3.22f1, 6000.5.8f1, 6000.6.0a1 (Doesn't support editing outside of UI Builder)

Tested on (OS): Windows 11 Pro (25H2)

Notes:

• Doesn't happen in normal scene Hierarchy
• Doesn't happen with elements dragged from UI Library window