Add search field to memory tooling

We should add a search field here so that users can search for the class they are looking for. I wanted to look at the instances of a specific class and had to manually scroll through the list.

No file or test is named. Start by locating the memory tooling screen and the class-instance list, then trace how that list is built. Done means users can enter a class name in a search field and see the matching class instances without manually scrolling; add or update tests if the screen has existing coverage.

Written by the indexing model from the issue text.