Add structfs action model classes

[dangunter]

Fixes

Fixes #1738

Summary/Motivation:

Changes proposed in this PR:

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[codecov]

Codecov Report

❌ Patch coverage is 94.66667% with 4 lines in your changes missing coverage. Please review.
✅ Project coverage is 73.85%. Comparing base (3b76abc) to head (1ec6608).

Files with missing lines	Patch %	Lines
idaes/core/util/structfs/runner_actions.py	94.59%	2 Missing and 2 partials ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1739      +/-   ##
==========================================
+ Coverage   73.84%   73.85%   +0.01%     
==========================================
  Files         406      406              
  Lines       66081    66125      +44     
  Branches    11110    11113       +3     
==========================================
+ Hits        48795    48835      +40     
- Misses      14745    14746       +1     
- Partials     2541     2544       +3     

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