JP-4313: Add NRC superstripe subarrays

[melanieclarke]

Toward JP-4313

Add new subarray names for upcoming NIRCam superstripe modes

Also add meta.exposure.read_times to the core schema to allow specification of explicit read times for unevenly sampled readouts. This is needed to support jump detection and ramp fitting for in-frame reads of repeated substripes.

Tasks

• update or add relevant tests
• update relevant docstrings and / or docs/ page
• Does this PR change any API used downstream? (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)
  • run jwst regression tests with this branch installed ("git+https://github.com/<fork>/stdatamodels@<branch>")

news fragment change types...

• changes/<PR#>.feature.rst: new feature
• changes/<PR#>.bugfix.rst: fixes an issue
• changes/<PR#>.doc.rst: documentation change
• changes/<PR#>.removal.rst: deprecation or removal of public API
• changes/<PR#>.misc.rst: infrastructure or miscellaneous change

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 90.66%. Comparing base (215ff88) to head (904f3c1).
⚠️ Report is 7 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #739   +/-   ##
=======================================
  Coverage   90.66%   90.66%           
=======================================
  Files          99       99           
  Lines        4619     4619           
=======================================
  Hits         4188     4188           
  Misses        431      431           

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[melanieclarke]

Regtests with jwst on main:
https://github.com/spacetelescope/RegressionTests/actions/runs/26599712397

Regtests with jwst branch + stcal updates:
https://github.com/spacetelescope/RegressionTests/actions/runs/26588854461

All passing.

[stscirij]

Should we also add the 4 new NIRSPEC subarrays here, or should they go into a separate PR?

[melanieclarke]

Should we also add the 4 new NIRSPEC subarrays here, or should they go into a separate PR?

I think we can make that a separate PR.

[braingram]

Changes LGTM. I consulted https://jira.stsci.edu/browse/APT-94701 for the subarray names but if there is a more definitive ticket let me know.

[melanieclarke]

Thanks for cross-checking, @braingram.