Returns the reasons why a document is invalidated.

• If expected_document_id is provided: returns motives linked to that expected document,
  motives linked to its document types, and global motives (unless with_global is False).
• If only document_type_id is provided (deprecated): returns motives linked to that
  document type and global motives (unless with_global is False).
• If neither is provided: returns only global motives (or empty if with_global is False).