PR: Geometry bugs for Curtain Walls since latest updates IFC exporter

### Problem Description

Hi,

Since the latest couple of updates for the IFC Exporter we encounter certain geometry bugs, despite the release notes covering to have fixed these.

IFC25.4.0.32 works fine. When I use 25.4.30.30 for the same model, it leaves out several geometries like the mullions and only showing the curtain wall panels. Could you please look into this and give us feedback?

With kind regards,

Koen

### Revit Version

2025.4.x

### IFC for Revit Addon Version

25.4.0

### Windows Version

11 25H2

Start by reproducing the report with the same model in IFC25.4.0.32 and 25.4.30.30 on Revit 2025.4.x. Compare the exported IFC files and confirm whether curtain-wall mullions and other omitted geometry are present; the issue is done when the newer exporter preserves the geometry or the failing model and regression point are identified.

Written by the indexing model from the issue text.