Rewriting an indat changes the results

[timothy-nunn]

The DICT_ICC_FULL was not being properly populated because it was using iteration variable (IXC) information... I have rewritten the get_constraint_equations function to use the ConstraintManager object directly to verify a constraint number is valid. DICT_ICC_FULL is therefore no longer used and I have removed it.

[codecov-commenter]

Codecov Report

❌ Patch coverage is 36.36364% with 7 lines in your changes missing coverage. Please review.
✅ Project coverage is 46.15%. Comparing base (c9a56cd) to head (5859d53).
⚠️ Report is 4 commits behind head on main.

Files with missing lines	Patch %	Lines
process/io/in_dat.py	36.36%	7 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #3901      +/-   ##
==========================================
- Coverage   46.38%   46.15%   -0.24%     
==========================================
  Files         123      123              
  Lines       28162    28841     +679     
==========================================
+ Hits        13064    13311     +247     
- Misses      15098    15530     +432     

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[clmould]

Looks good, only a couple minor changes then will merge :)