Documentation of visualization tools

[eecharlie]

The documentation has a catalog of 3rd party visualizations linked near the beginning, yet it emerges quickly that ocp_vscode is the canonical approach used throughout the examples. For me it would have been quite helpful if:

• The documentation unambiguously pointed to ocp_vscode as the recommended if not practically required visualization tool to follow the docs/examples
• Basic pointers were given about using it. For example, the first appearance I see is at https://build123d.readthedocs.io/en/latest/key_concepts.html but the examples are code snippets that don't show what imports are needed other than implicitly build123d. If you want to be a bit more beginner-friendly, the code snippet examples should run on their own if copy-pasted
• Additionally, a small but important basic workflow for using ocp_vcode is to use show_clear(), otherwise every shown object is added and persisted in the visualization port. It may make sense to at least demonstrate a workflow of show_clear() preceding every example that uses show_object() if not add that to all the examples

There is a note about using ocp-vscode to install build123d, but this is easy to miss if you're struggling through getting this to work on Apple Silicon and implies ocp-vscod is optional. In fact I think any of the visualizers are going to get hung up on the the same Apple Silicon issue