[Repo Assist] ci: update actions/checkout v2→v4 (Linux) and codecov-action v2→v5

[github-actions]

🤖 This is an automated PR from Repo Assist.

Problem

Two CI workflow issues were identified:

1. Inconsistency: The Linux job used actions/checkout@v2 while the Windows job already used actions/checkout@v4. This means the Linux job was using a much older action version, which could lead to subtle differences in behaviour.

2. Outdated Codecov action: codecov/codecov-action@v2 uses the legacy Codecov uploader which was deprecated and may be the cause of the long-standing upload failures noted in issue Codecov upload seems to be broken with the latest altcover version #191.

Changes

• Linux job: actions/checkout@v2 → actions/checkout@v4 (aligns with Windows job)
• Windows job: codecov/codecov-action@v2 → codecov/codecov-action@v5 (new Codecov uploader)
• Removed deprecated directory: ./ parameter (superseded by the explicit files: setting which was already present)
• Moved CODECOV_TOKEN to the recommended env: block (required by v4+)

Notes on CODECOV_TOKEN

codecov/codecov-action@v5 recommends passing the token via CODECOV_TOKEN env var. If the CODECOV_TOKEN secret is not configured in the repository settings, coverage upload will be skipped gracefully (CI won't fail). To enable uploads, add the token from (app.codecov.io/redacted)

Test Status

This is a CI configuration change — no code changes, so no tests to run. The action version bumps are non-breaking for their respective interfaces. The Codecov parameter change (directory removed, CODECOV_TOKEN added) matches the v5 recommended configuration.

Closes #191

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Warning

Protected Files — Push Permission Denied

This was originally intended as a pull request, but the patch modifies protected files. A human must create the pull request manually.

Protected files

• .github/workflows/build-and-test.yml

The push was rejected because GitHub Actions does not have workflows permission to push these changes, and is never allowed to make such changes, or other authorization being used does not have this permission.

Create the pull request manually

# Download the patch from the workflow run
gh run download 23945548931 -n agent -D /tmp/agent-23945548931

# Create a new branch
git checkout -b repo-assist/ci-update-checkout-codecov-20260403-73102d1942b2e119 developer

# Apply the patch (--3way handles cross-repo patches)
git am --3way /tmp/agent-23945548931/aw-repo-assist-ci-update-checkout-codecov-20260403.patch

# Push the branch and create the pull request
git push origin repo-assist/ci-update-checkout-codecov-20260403-73102d1942b2e119
gh pr create --title '[Repo Assist] ci: update actions/checkout v2→v4 (Linux) and codecov-action v2→v5' --base developer --head repo-assist/ci-update-checkout-codecov-20260403-73102d1942b2e119 --repo fslaborg/FSharp.Stats

Generated by 🌈 Repo Assist, see workflow run. Learn more.

To install this agentic workflow, run

gh aw add githubnext/agentics/workflows/repo-assist.md@4ea8c81959909f40373e2a5c2b7fdb54ea19e0a5