PR: PartitioningType of IfcWindowType not exported to IFC4

### Problem Description

The ```PartitioningType``` attribute is exported to ```IfcWindowStyle``` in IFC2x3 CV2, but not to ```IfcWindowType``` in IFC4 RV Arch. I haven't tested for ```IfcWindow``` since we only define this attribute on the type level.

- Tested in 25.4.4
- Test file: https://github.com/andydandy74/MyIssues/blob/master/RevitIFC922/190_WindowPartitioningTypeIFC4.rvt

#### IFC2x3

#### IFC4

### Revit Version

2025.4.x

### IFC for Revit Addon Version

25.4.0

### Windows Version

11 24H2

Start with the linked Revit test file and compare its IFC2x3 and IFC4 exports, focusing on the PartitioningType attribute for the window type. Trace the IFC4 export path in the add-on and verify that the resulting IfcWindowType contains the expected PartitioningType value without changing the existing IFC2x3 behavior.

Written by the indexing model from the issue text.