Method loadConfig

pj_app/tests/msgbox_mock_source.cpp:30–33

  }

  PJ::Status loadConfig(std::string_view config_json) override {
    config_ = std::string(config_json);
    return PJ::okStatus();
  }

  PJ::Status importData() override {
    // config_ is opaque to this example (no JSON dependency); the marker is