Allow the user to select a widget to inspect from their code

This feature can be more efficient than selecting in the tree view or from the screen, when the user knows exactly which widget they want to inspect.

The issue describes selecting a widget for inspection from source code instead of the tree view or screen. Start by locating the existing widget-inspection entry points and how those selection paths identify widgets; done means a user can select a widget from their code and inspect it.

Written by the indexing model from the issue text.