code: public function run(): void
      {
          if (!$this->isRan) {
              $this->isRan = true;
              foreach ($this->items as $item) {
                  $options      = $item[2] ?? [];
                  $ruleName = $item[1];
                  foreach (is_array($item[0]) ? $item[0] : [$item[0]] as $fieldName) {
                      self::applyRuleToField($fieldName, $ruleName, $options);
                  }
              }
          }
      }
docs: The main executable method.
  @return void