JP-4224: Remove correction_pars

[melanieclarke]

Resolves JP-4224

Remove unnecessary storage of correction models as an attribute on the following steps: flat_field, pathloss, barshadow, photom, and master_background_mos.

Just recomputing the corrections instead of storing them only adds a small amount of processing time to the master_background_mos step (~4s running the regtest example locally), but it improves peak memory use in stage 2 for all modes that use these steps.

Discussion still needed about whether we need to deprecate these attributes. So far, I have just removed them, but I can add deprecation support back in.

This PR is built on top of #10421, since they touch the same step and the additional unit test coverage was useful here. I can separate them out if need be. (those changes have been merged; this PR is rebased)

Initial regression tests here:
https://github.com/spacetelescope/RegressionTests/actions/runs/24090988005
There is one header diff for master background MOS processing, because the interpolated flat is recreated instead of provided as a custom reference file. I think the existing value was misleading anyway. Also shows memory improvements above the threshold for NIRCam imaging and spectra as well as NIRISS SOSS.

Tasks

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  • update or add relevant tests
  • update relevant docstrings and / or docs/ page
  • start a regression test and include a link to the running job (click here for instructions)
    • Do truth files need to be updated ("okified")?
      • after the reviewer has approved these changes, run okify_regtests to update the truth files
• if a JIRA ticket exists, make sure it is resolved properly

[codecov]

Codecov Report

❌ Patch coverage is 98.64865% with 1 line in your changes missing coverage. Please review.
✅ Project coverage is 86.38%. Comparing base (f86541f) to head (83a7cd8).

Files with missing lines	Patch %	Lines
jwst/barshadow/bar_shadow.py	83.33%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #10432      +/-   ##
==========================================
- Coverage   86.40%   86.38%   -0.02%     
==========================================
  Files         373      373              
  Lines       40112    40062      -50     
==========================================
- Hits        34658    34608      -50     
  Misses       5454     5454              

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[tapastro]

I'm in favor of moving forward here. Just needs a conflict to be resolved and to be pulled out of draft.

[melanieclarke]

New regression test run:
https://github.com/spacetelescope/RegressionTests/actions/runs/25341328675

Just the one expected header diff, for the master_background_mos test.