AT:

• the request to the backend for evaluating a report and retrieving the flow node names can be performed in a batch (will be done with OPT-2058)
• the front-end reads the flow node names from the evaluation request

Context:
Optimize has currently a lag, because the front-end does several requests in a row to the back-end: one for the evaluation and one to get the flow node names. With OPT-2058 the flow node names are added to the evaluation response, so we should directly use those.