[Problem] Objects generated using Assembly4's mirror function cannot be exported to GLB, STP,ifc

[oursland]

Issue originally by @3xxx on my backup mirror.

[code]
OS: Windows 10 build 19044
Word size of FreeCAD: 64-bit
Version: 2024.1006.0.14555 (Git shallow)
Build type: Release
Branch: (HEAD detached at 20241003stable)
Hash: a9810d509a6f112b5ac03d4d4831b67e6bffd5b7
Python 3.11.8, Qt 5.15.8, Coin 4.0.1, Vtk 9.2.6, OCC 7.7.2
Locale: Chinese/China (zh_CN)
Installed mods: 
  * A2plus 0.4.66
  * A2plus.backup1724687131.225395 0.4.64 (Disabled)
  * Assembly3 0.12.2
  * Assembly4.backup1724683001.0928686 0.50.9 (Disabled)
  * Assembly4.backup1741840888.0637093 0.50.15
  * BillOfMaterials 0.0.7
  * Help 1.0.3
[/code]

Hi @oursland :
I found that FreeCAD can't export Assembly4 mirror part in assembly4's catalog to stp OR glb OR ifc file correctly.
I've found that both linear array and ring array can be exported correctly, but mirror array body does not carry placement and angle information.
And also mirror_body can export correctly, but mirror_part cant export correctly like the picture:

testmirror_assembly.zip

[leoheck]

I've noticed the same happens to Bodies when using Mirror of a Mirror.

When importing it, I can only see this:

[leoheck]

This is strange, but it is an issue with FreeCAD itself.
In the operation above, for instance, if I mirror YZ and then XZ, then after importing the step, I see only the YZ mirrored. Alternatively, if I do XZ and then YZ, after importing it, I see only XZ mirrored.