Add 'Soak Matrix' widget

Related to adding time-based system tests, we will want to run variations of these time-based tests to determine / visualize / tune optimal amount of time required that may cause failures (find issues) (in XX minutes).

This feature can be a building block to further experiments and investigation, including defect injection and using information to potentially train a DL model to optimize time-based tests to fail in least number of minutes.

No files, tests, or entry points are named. Start by locating the existing time-based system tests and any widget or visualization code, then clarify the matrix dimensions, failure criteria, and expected output; done means a defined and usable Soak Matrix widget.

Written by the indexing model from the issue text.