cli benchmark path tests

[ahmdkaml]

Summary of Changes

Added comprehensive test coverage for faircode/cli.py's benchmark subcommand (lines 245–283) in tests/test_cli.py[cite: 1]:

• Missing Dependencies Handling: Verified that importing without the benchmark extra catches ImportError and outputs the pip install faircode[benchmark] install guide to stderr[cite: 1].
• Paper-Run Drift Warning: Verified that non-default --n-resamples / --n-permutations trigger the reproducibility drift warning on stderr[cite: 1].
• Missing Manifest Error Path: Confirmed the exit code and error message when no audit.yaml files are found under the search root[cite: 1].
• CLI Success Execution: Validated the complete CLI execution against German Credit Lending/audit.yaml, confirming exit code 0, summary output on stderr, and artifact generation (results_fairness.csv, results_performance.csv, summary.csv)[cite: 1, 2].

[vercel]

@ahmdkaml is attempting to deploy a commit to the yashkewlani2020-gmailcom's projects Team on Vercel.

A member of the Team first needs to authorize it.

[github-actions]

@yakew7 - new PR touching a path you own, please review.