docs: fix outdated documentation (automated weekly drift check)

[Miyamura80]

Fixes documentation drift where the GitHub Actions workflow status badge in README.md was pointing to a renamed workflow file (test_target_tests.yaml -> a_test_target_tests.yml).

Followed the OUTDATED_DOCUMENTATION_GUIDELINE.md strictly to only fix verifiably incorrect factual references.

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PR created automatically by Jules for task 17764249263775210469 started by @Miyamura80

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[greptile-apps]

Greptile Summary

This PR fixes a stale GitHub Actions workflow badge in README.md, updating the referenced workflow filename from the old test_target_tests.yaml to the current a_test_target_tests.yml. The fix is verified — .github/workflows/a_test_target_tests.yml exists in the repository, and the old filename does not. No logic or functionality is affected; this is a pure documentation correction.

Confidence Score: 5/5

• This PR is safe to merge — it is a single-line documentation fix with no code or logic changes.
• The change is minimal and verifiably correct: the new badge URL points to a_test_target_tests.yml, which exists in .github/workflows/, while the old filename test_target_tests.yaml no longer exists. No risk of regressions.
• No files require special attention.

Important Files Changed

Filename	Overview
README.md	Updates the GitHub Actions workflow status badge URL from the outdated test_target_tests.yaml to the correct a_test_target_tests.yml, which matches the actual workflow file present in .github/workflows/.

_{Last reviewed commit: a5a6db4}