JP-3915: Bugfix to SIRS kernel subtraction

[drlaw1558]

Resolves JP-3915 indexing bug.

Tasks

• request a review from someone specific, to avoid making the maintainers review every PR
• add a build milestone, i.e. Build 11.3 (use the latest build if not sure)
• Does this PR change user-facing code / API? (if not, label with no-changelog-entry-needed)
  • write news fragment(s) in changes/: echo "changed something" > changes/<PR#>.<changetype>.rst (see below for change types)
  • 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

[drlaw1558]

Still testing, but PR open to invite feedback.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 72.56%. Comparing base (97db183) to head (0bfedac).
Report is 5 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #9267   +/-   ##
=======================================
  Coverage   72.56%   72.56%           
=======================================
  Files         371      371           
  Lines       37167    37167           
=======================================
  Hits        26970    26970           
  Misses      10197    10197           

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[drlaw1558]

Ok, have now tested this on NIRCAM SW/LW, NIRISS, and NIRSpec data.

[melanieclarke]

Thanks for the fix - I'll run regression tests in a moment.

Side note - in the future, can you please leave the task list in the PR description when you send it in? It's helpful for reviewers to remember all the necessary steps. I'll add it back in to this one.

[melanieclarke]

Regression tests running here:
https://github.com/spacetelescope/RegressionTests/actions/runs/13796320910

[melanieclarke]

Looks like the only regression test failure is for the NIRCam image SIRS test - it looks like it makes a small difference to the test case, which I assume is expected.