Expose analysis plies under SolidModel and ImportedSolidModel

[roosre]

📝 Description of the feature

The analysis plies of (imported) solid model are not accessible in the Python frontend. List of plies can contain in the case of a Solid Model Analysis Plies and Interface Layers, Analysis Plies and ImportedAnalysisPlies in case of an ImportedSolidModel.
Simplify examples (Imported Plies, Imported Solid Model and Solid Model) by retrieving the analysis plies directly from the solid mode instead via the original modeling ply.

💡 Steps for implementing the feature

No response

🔗 Useful links and references

No response

[greschd]

This will require some backend changes:

• for the Interface Layer and Imported Analysis Ply, exposure on the (Imported) Solid Model is not yet implemented -> added backend work item
• for the Analysis Ply on an Imported Solid Model, I am getting the following error: Analyis-ply has no parent production-ply!. The reason for this is that filler plies don't have a correspondence in the Modeling Group hierarchy (and thus no production ply parent). This will need to be addressed in the backend. -> added backend bug
• I think the regular Solid Model can (maybe?) also contain Imported Analysis Ply objects.

Analysis plies on SM seem to work as expected.

WIP branch: feat/plies_on_solid_models

Related: #7