Function validate_example_folder_readmes 

pub fn validate_example_folder_readmes(
    share_root: &Path,
) -> Result<Vec<ExampleReadmeViolation>, ExamplesDiscoverError>

Audit every immediate child directory under {share_root}/examples/ for a README.md whose YAML frontmatter satisfies the discovery contract (name + description).

Optional examples/README.md (base-folder doc) is validated when present.

Errors

Returns ExamplesDiscoverError when the examples directory cannot be read.