Function gather_matching_file_violations

pub fn gather_matching_file_violations(
    nodes: &[ProjectedNode],
    check_filter: &Filter,
    is_negated: bool,
) -> Vec<Violation>

Judges selected files against one filename, folder, or path requirement.

Positive rules report non-matches and negated rules report matches. An empty selection remains empty here; the terminal layer, rather than this pure predicate, is responsible for reporting an empty test.