remove some verbose print() calls

[ManuelHu]

I focused on the small number of print statements that are always triggered with our usage, but that do not provide any additional value to us.

I replaced the prints in the global scope with warnings or exceptions that are only triggered if the user attempts to use the data structures that depend on the imported modules.

[codecov]

Codecov Report

Attention: Patch coverage is 35.29412% with 11 lines in your changes missing coverage. Please review.

Project coverage is 74.09%. Comparing base (ebbcc37) to head (f323975).
Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
src/pyg4ometry/analysis/Data.py	38.46%	8 Missing ⚠️
src/pyg4ometry/visualisation/UsdViewer.py	25.00%	3 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #219      +/-   ##
==========================================
- Coverage   74.12%   74.09%   -0.03%     
==========================================
  Files         157      157              
  Lines       22739    22752      +13     
==========================================
+ Hits        16855    16859       +4     
- Misses       5884     5893       +9     

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[gipert]

Thanks @ManuelHu, I wanted to do this as well. I have opened #220, which is related. I'll merge and tag a new patch release since this is only about cosmetics.