docs: def _traverse_report(data):
      """Recursively traverse vehicle health report."""
      if 'items' not in data:
          return {}
      out = {}
      for item in data['items']:
          skip = (item['severity'] == 'NonDisplay' or
                  item['itemKey'] == 'categoryDesc' or
                  item['value'] in [None, 'Null', 'N/A', 'NULL'])
          if skip:
              continue
          value = 'Ok' if item['value'] == '0.0' else item['value']
          out[item['itemKey']] = value
          out.update(_traverse_report(item))
      return out