Add __all__ for non-test and non-doc modules

[pllim]

Closes #9385

Unless users are doing star imports on the affected modules, which they should not in the first place, there is no change that needs to be documented in change log.

grep "__all__" -Lr . | grep "\.py" | grep -v "test" would tell you most of them, minus a couple of obvious ones you can ignore.

Partially assisted by generate_all.

TODO

• Add __all__ to remaining modules.
• grep again to make sure I didn't miss anything.

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)
  • 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) https://github.com/spacetelescope/RegressionTests/actions/runs/16352650200 and https://github.com/spacetelescope/RegressionTests/actions/runs/16427411316
    • 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

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 80.44%. Comparing base (5d07960) to head (23d9688).
⚠️ Report is 322 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #9646      +/-   ##
==========================================
+ Coverage   80.37%   80.44%   +0.07%     
==========================================
  Files         367      367              
  Lines       37265    37407     +142     
==========================================
+ Hits        29951    30093     +142     
  Misses       7314     7314              

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[melanieclarke]

This all looks fine to me. Setting up __all__ should do no harm, and we can always add or remove to what's included here as we go. I checked, and it looks like the changes here do not impact documentation for the places we've included automodapi.

Thanks again for tidying up!