Function cpp_sentinel_recovered_classes 

pub fn cpp_sentinel_recovered_classes(
    root: Node<'_>,
    source: &str,
) -> Vec<CppSentinelRecoveredClass>

Recover the class and out-of-line owner scopes from every malformed namespace-sentinel region in root.

This is the shared structural counterpart to [CppDeclarationVisitor::visit_nested_namespace_sentinel]. It intentionally reuses the visitor’s sentinel/class admission predicates instead of parsing source text a second time. The returned values own only ranges and names, so they can be retained by an inverted usage scan after the tree borrow ends.