TokaMaker: Add error handling to .save_eqdsk() (failed tracing)

[hansec]

This pull request adds error handling to OpenFUSIONToolkit.TokaMaker.TokaMaker.save_eqdsk()

Additionally, the following changes to the core code were made:

• Update error reporting in TokaMaker.get_q() to report flux coordinate where tracing failed

This pull request does not modify any existing APIs or input file settings.

[codecov]

Codecov Report

Attention: Patch coverage is 0% with 21 lines in your changes missing coverage. Please review.

Project coverage is 53.2%. Comparing base (98c0492) to head (4deab85).

Files	Patch %	Lines
src/physics/grad_shaf_util.F90	0.0%	14 Missing ⚠️
src/python/OpenFUSIONToolkit/TokaMaker/_core.py	0.0%	4 Missing ⚠️
src/python/wrappers/tokamaker_f.F90	0.0%	3 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##            main     #68     +/-   ##
=======================================
- Coverage   53.3%   53.2%   -0.1%     
=======================================
  Files        128     128             
  Lines      42330   42345     +15     
=======================================
  Hits       22563   22563             
- Misses     19767   19782     +15     

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