Simulator GUI: Save form parameters when launching a scenario

As a user of the simulator GUI I would like to preserve the form values I enter before launching a scenario so that I can reuse the form values from a previous launch later on without having to re-enter all the data again

Background:
* when testing or retesting a particular scenario the form parameters sometimes differ very little or not at all between each launch. If a tester could decide what forms should be saved when launching a scenario they could then select one of these from a list of saved launches when re-launching later on.

No files or tests are named. Start by locating the simulator GUI's scenario-launch form and launch flow, then determine how saved form values and a selectable list should behave; done means users can choose which launch parameters to preserve and reuse them later without re-entering the data.

Written by the indexing model from the issue text.