JP-4326: Allow multi-band direct imaging input to wfss_contam

[emolter]

Resolves JP-4326

Requires spacetelescope/stdatamodels#756

This PR adds a user reprocessing option to the WfssContamStep that allows passing a multi-wavelength direct image cube into the step instead of a single direct image. This allows the simulated dispersed flux to have an arbitrary spectral shape instead of always assuming a flat spectrum. See the ticket and docstring for more details.

Tasks

• If you have a specific reviewer in mind, tag them.
• add a build milestone, i.e. Build 12.0 (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 changelog readme for instructions)
    • if your change breaks step-level or public API (as defined in the docs), also add a changes/<PR#>.breaking.rst news fragment
  • 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 98.24561% with 1 line in your changes missing coverage. Please review.
✅ Project coverage is 86.87%. Comparing base (8ed53cf) to head (7775125).
⚠️ Report is 3 commits behind head on main.

Files with missing lines	Patch %	Lines
jwst/wfss_contam/observations.py	92.30%	1 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##             main   #10463   +/-   ##
=======================================
  Coverage   86.87%   86.87%           
=======================================
  Files         375      375           
  Lines       40347    40396   +49     
=======================================
+ Hits        35050    35096   +46     
- Misses       5297     5300    +3     

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[melanieclarke]

@emolter - I think this branch is intended for INS to test a possible solution, but there are some conflicts. Can we clean it up?

[emolter]

Thanks for the bump Melanie, merge should be done now. FYI at the WFSS working group meeting it sounded like there won't be personnel to test this until after the build deadline, so we've deferred it to build 13.2. I removed the 13.0 tag already. But point well taken that I should periodically ensure it's up-to-date with other changes.

[emolter]

regtests with spacetelescope/stdatamodels#756: https://github.com/spacetelescope/RegressionTests/actions/runs/27351610540

Not sure what's up with the two association test failures, as I did not touch the asns at all here.