Show standard error for failing CWL jobs that capture standard error

[adamnovak]

This fixes #2994 by logging standard error from CWL tasks to the Toil log, when the tasks fail, even if standard error for the task is being captured to a file.

(When standard error is not captured, we already log it to the Toil log.)

The result looks just like if it wasn't being captured:

[2026-07-16T17:15:05-0400] [Thread-4 (statsAndLoggingAggregator)] [I] [toil.statsAndLogging] fail_with_log.cwl.hello._:640ebd69-f2a0-4ed6-a923-4b450915dd90.stderr follows:
=========>
	Message: This is a test
<=========

We don't do this when the job succeeds, because the user might be capturing the log because it's inconveniently large.

Changelog Entry

To be copied to the draft changelog by merger:

• CWL job error logs are now reported for failing jobs even if the job's standard error is captured to a file.

Reviewer Checklist

• Make sure it is coming from issues/XXXX-fix-the-thing in the Toil repo, or from an external repo.
  • If it is coming from an external repo, make sure to pull it in for CI with:

    contrib/admin/test-pr otheruser theirbranchname issues/XXXX-fix-the-thing
    

  • If there is no associated issue, create one.
• Read through the code changes. Make sure that it doesn't have:
  • Addition of trailing whitespace.
  • New variable or member names in camelCase that want to be in snake_case.
  • New functions without type hints.
  • New functions or classes without informative docstrings.
  • Changes to semantics not reflected in the relevant docstrings.
  • New or changed command line options for Toil workflows that are not reflected in docs/running/{cliOptions,cwl,wdl}.rst
  • New features without tests.
• Comment on the lines of code where problems exist with a review comment. You can shift-click the line numbers in the diff to select multiple lines.
• Finish the review with an overall description of your opinion.

Merger Checklist

• Make sure the PR passed tests, including the Gitlab tests, for the most recent commit in its branch.
• Make sure the PR has been reviewed. If not, review it. If it has been reviewed and any requested changes seem to have been addressed, proceed.
• Merge with the Github "Squash and merge" feature.
  • If there are multiple authors' commits, add Co-authored-by to give credit to all contributing authors.
• Copy its recommended changelog entry to the Draft Changelog.
• Append the issue number in parentheses to the changelog entry.

[mr-c]

Epic PR, nice re-org!

[mr-c]

some typos :-)