Updated timing pattern

[t-brandt]

Closes #

This PR improves the timing pattern for the detectors, primarily for the purpose of making the WFI18 transient correction more accurate. The approach implemented is almost as accurate as using the guide window MA tables, but avoids having to read these reference files in for now. There is a fudge factor of 1.5 passed to the timing pattern to account for the fact that the WFI18 transient decays slightly more quickly when reading out the guide window.

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
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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 80.58%. Comparing base (1937ff3) to head (d8346c0).

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2316      +/-   ##
==========================================
+ Coverage   80.55%   80.58%   +0.02%     
==========================================
  Files         155      155              
  Lines        9398     9409      +11     
==========================================
+ Hits         7571     7582      +11     
  Misses       1827     1827              

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[schlafly]

Thanks Tim. There's a missing definition of npad that is breaking the tests. The logic here has gotten involved enough that some testing probably makes sense but I'll defer to you, thanks.

[schlafly]

Running regression tests here: https://github.com/spacetelescope/RegressionTests/actions/runs/25677644827 . They show some minor differences ~everywhere due to the dark decay step being an early step, and this timing pattern affecting the dark decay step.

[schlafly]

This has minor impacts across a lot of regtest files, that get amplified by bad linearity corrections. The only ones that are actually noticeable are on WFI18, which has the effect that depends sensitively on the timing pattern. There we see the expected 256 pixel pattern. Approving and merging.