Implement road spatial structure menu in FragmentTree

[agviegas]

Description 📝

IFC roads have their own spatial structure, just like buildings. A file with both buildings and roads should be supported, and all structures should be displayed in the FragmentTree menu.

Suggested solution 💡

No response

Alternative ⛕

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Additional context ☝️

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Validations ✅

• [X] Read the docs.
• [X] Check that there isn't already an issue that requests the same feature to avoid creating a duplicate.