feat: replace support of "datetime_filesafe" format field in output file prefix format string with "datetime"

[candleindark]

This PR closes #304

[Copilot]

Pull request overview

This PR replaces the datetime_filesafe format field with datetime in the output file prefix format string throughout the codebase. The change maintains backwards compatibility by still accepting datetime_filesafe in the LogPaths.create() method while promoting datetime as the new standard. The actual datetime format remains unchanged (still file-safe: %Y.%m.%dT%H.%M.%S).

Changes:

• Updated default DUCT_OUTPUT_PREFIX to use {datetime} instead of {datetime_filesafe}
• Modified LogPaths.create() to support both {datetime} and {datetime_filesafe} format fields for backwards compatibility
• Updated documentation in CLI help text and README to reflect the new {datetime} field name

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 3 comments.

File	Description
src/con_duct/duct_main.py	Updated default prefix constant and modified LogPaths.create() to accept both datetime and deprecated datetime_filesafe fields
src/con_duct/cli.py	Updated CLI help text to remove reference to datetime_filesafe and show only datetime as a supported format field
README.md	Updated documentation examples and help text to use {datetime} instead of {datetime_filesafe}
test/duct_main/test_log_paths.py	Updated test to use new {datetime} format field instead of {datetime_filesafe}

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 91.63%. Comparing base (3756590) to head (c33b398).

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #375   +/-   ##
=======================================
  Coverage   91.63%   91.63%           
=======================================
  Files          15       15           
  Lines        1112     1112           
  Branches      138      138           
=======================================
  Hits         1019     1019           
  Misses         70       70           
  Partials       23       23           

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[yarikoptic]

conflicts came up

[asmacdo]

yep we'll need to rebase (i moved this). either I will do or @candleindark on Friday?

[Copilot]

Pull request overview

Copilot reviewed 5 out of 5 changed files in this pull request and generated 2 comments.

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[candleindark]

@asmacdo Have you seen the error at https://github.com/con/duct/actions/runs/21525492435/job/62027909892?pr=375 before? It seems to be an unrelated issue.

It can be an intermittent failure, but I can't rerun tests in this repo to find out if that's the case.

[candleindark]

I couldn't reproduce the error on my own Mac, but my Mac is not an Intel Mac though.

[asmacdo]

@candleindark yep I think this one just needs a rerunflake back off #384

[asmacdo]

Reran the failing test, and it still failed, so I've added the backoff logic to that one. #394 after we merge that we should be good here.