Function auto_detect_cases 

pub fn auto_detect_cases(
    project_root: &ProjectRoot,
    registry: &ExtractorRegistry,
    resolvers: &ResolverRegistry,
) -> Vec<BenchCase>

Auto-generate benchmark cases by scanning the project.

1. Scan for test files → extract-vs-cat case
2. Try other extractors (express, react, go-http, go-test) → extract-vs-cat case

Users can add comparison commands (grep, ast-grep, etc.) via --baseline or .config/aql.bench <baseline type="command" .../> entries.