Fix polyhedron vertices - points

[ericgozzi]

Fixes the vertices setter to convert list[Point] into a list of coordinates list[list[int]]. The Polyhedron.vertices attribute now always returns a list of vertices (list[list[int]]).

The behavior now matches the docstring.

• Added a new test test_polyhedron_vertices in test_polyhedron.py to verify that the Polyhedron class correctly handles both lists of coordinates and lists of Point objects as vertices.
• Imported Point in the test file to support the new test case.

What type of change is this?

• Bug fix in a backwards-compatible manner.
• New feature in a backwards-compatible manner.
• Breaking change: bug fix or new feature that involve incompatible API changes.
• Other (e.g. doc update, configuration, etc)

Checklist

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• I added a line to the CHANGELOG.md file in the Unreleased section under the most fitting heading (e.g. Added, Changed, Removed).
• I ran all tests on my computer and it's all green (i.e. invoke test).
• I ran lint on my computer and there are no errors (i.e. invoke lint).
• I added new functions/classes and made them available on a second-level import, e.g. compas.datastructures.Mesh.
• I have added tests that prove my fix is effective or that my feature works.
• I have added necessary documentation (if appropriate)

[gonzalocasas]

mmm... this has two problems:

1. performance is not the best, because it iterates twice over all vertices (first to check all() and then to convert to lists), and
2. [this is a bit more problematic] vertices are not always going to be instances of Point, compas accepts lists/tuples/etc that can be iterated as valid points, so, this code would break that assumption

may I ask what's the trigger for changing this? Have you observed a bug in other code?