fix(plotting): Improve interface of the plotting class.

[AlejandroFernandezLuces]

Description

This PR improves the usability of some methods in the plotting class. This class was meant to be used inside eplot, vplot.. functions, but since some use cases involve using it standalone, I improved it's usability and documentation.

Checklist

• I have visited and read Develop PyMAPDL.
• I have tested my changes locally
• I have added necessary documentation or updated existing documentation.
• I have followed the PyMAPDL coding style guidelines.
• I have added appropriate unit tests that also ensure the minimal coverage criteria.
• I have reviewed my changes before submitting this pull request.
• I have linked the issue or issues that are solved to the PR if any.
• I have assigned this PR to myself.
• I have marked this PR as draft if it is not ready to be reviewed yet.
• I have made sure that the title of my PR follows Commit naming conventions (e.g. feat: adding new MAPDL command)

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[codecov]

Codecov Report

Attention: Patch coverage is 76.47059% with 4 lines in your changes missing coverage. Please review.

Project coverage is 88.05%. Comparing base (c943198) to head (dd79733).

❌ Your patch check has failed because the patch coverage (76.47%) is below the target coverage (90.00%). You can increase the patch coverage or adjust the target coverage.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #3702      +/-   ##
==========================================
- Coverage   88.12%   88.05%   -0.07%     
==========================================
  Files         187      187              
  Lines       14707    14716       +9     
==========================================
- Hits        12960    12958       -2     
- Misses       1747     1758      +11     

[AlejandroFernandezLuces]

@clatapie This PR fixes your original issue. I'm unsure if more issues will arise, since plots are not throwing errors and I do not know how plots should look like. I would need to compare results from the original examples to what we have right now for further debugging.

From my point of view, we can either merge this PR and we can add more fixes as issues arise, or you can install this branch in your local and ping me when something does not look as expected. What do you think?

[clatapie]

Thanks for fixing the error @AlejandroFernandezLuces!
I will use this branch in the PyMAPDL-Example PR and check the documentation output so that we will have it tested with a broader range of examples