Method root_cause

mllm-kernel/include/mllm_kernel/utils.hpp:71–75

 public:
  explicit PanicError(const std::string& msg) : runtime_error(msg), message_(msg) {}
  [[nodiscard]] auto root_cause() const -> std::string_view {
    const auto str = std::string_view{message_};
    const auto pos = str.find(": ");
    return pos == std::string_view::npos ? str : str.substr(pos + 2);
  }

 private:
  std::string message_;