MSVC: Windows compatibility

[jhunkeler]

Resolves SCSB-201

This PR makes it possible to compile stcal using MSVC/MSBuild on Windows.

• MSVC does not support Variable Length Arrays (ref)
• POSIX resource management functions do not exist on Windows (sys/resource.h, etc.).
  • If need be, we can implement the same functionality using the Windows API

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 regression tests with this branch installed ("git+https://github.com/<fork>/stcal@<branch>")
    • jwst regression test
    • romancal regression test

news fragment change types...

• changes/<PR#>.apichange.rst: change to public API
• changes/<PR#>.bugfix.rst: fixes an issue
• changes/<PR#>.general.rst: infrastructure or miscellaneous change

[codecov]

Codecov Report

Attention: Patch coverage is 33.33333% with 12 lines in your changes missing coverage. Please review.

Project coverage is 89.35%. Comparing base (bb57168) to head (1c9127f).
Report is 24 commits behind head on main.

Files with missing lines	Patch %	Lines
setup.py	0.00%	10 Missing ⚠️
src/stcal/outlier_detection/median.py	71.42%	2 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #351      +/-   ##
==========================================
- Coverage   89.41%   89.35%   -0.06%     
==========================================
  Files          64       64              
  Lines       10143    10172      +29     
==========================================
+ Hits         9069     9089      +20     
- Misses       1074     1083       +9     

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.

[pllim]

Should add a Windows build here to prove this PR works. 😉

stcal/.github/workflows/ci.yml

Line 31 in 583930c

envs: |

[mcara]

Amazing!

[jhunkeler]

Of course the moment I decide to add Windows into the mix:
python/cpython#135151

[pllim]

You finally get to the fun stuff:

assert str(arr._filename).split("/")[-1] in os.listdir(tempdir)

and

>       return io.open(self, mode, buffering, encoding, errors, newline)
               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
E       PermissionError: [Errno 13] Permission denied: 'C:\\...\\test_disk_appendable_array_bad0\\tmptest'

[jhunkeler]

Tada.
https://github.com/spacetelescope/stcal/actions/runs/15644177990/job/44078328011?pr=351

[pllim]

Maybe this warrants a change log so Windows user can read it and be happy.

[pllim]

FWIW green job is good enough for merge. We can always follow-up later if there is any Windows intricacies to fix later (I think that is going to get smoke out if downstream also start doing regression tests in Windows 👹). But since I am not maintainers, I'll leave approval and merge to someone else. Thanks!