Make MeshCoords immutable and sync updates with the attached mesh

[ESadek-MO]

🚀 Pull Request

Description

Closes #4757, continues #6125.

This pull request aims to make MeshCoords immutable, and when it's corresponding Mesh updates, for the MeshCoord to refresh its Points, Bounds, and Metadata from the Mesh.

Notes to self

• First problem, where node had no bounds, has been solved.
• Next problem is that bounds aren't being rendered in the cml (and presumably, don't exist). There wasa thread to pull, in that bounds is set to an error message about bounds_dm, but it seems like that's a red herring, and is solved within __init__.
• There's a chance this only solves another 10 or so errors, but progress is progress