PR: IsExternal for IfcWindows faulty

### Problem Description

IsExternal for IfcWindows returns seemingly random results.
The problem seems to be the following:

- For some windows CategoryUtil.IsElementExternal return the correct result (determined via the host wall)
- Then the WindowsType is exported and since it has no parameters or host a host wall it defaults to false
- Windows that are exported henceforth adopt the value fo the type via IsExternalParameterValueCache and do not look at the host wall anymore

Currently the solution is to add an appropriate parameter to the type and/or the instance of a window.

### Revit Version

2024.0.x

### IFC for Revit Addon Version

24.x.x

### Windows Version

11 22H2

Reproduce the issue in Revit 2024 with IFC for Revit 24.x, then trace CategoryUtil.IsElementExternal and IsExternalParameterValueCache for window instances and types. Done means exported windows consistently use the host wall result instead of inheriting an incorrect type fallback.

Written by the indexing model from the issue text.