Studio diagnostics should show the containing member or event

Studio's diagnostics panel currently shows the severity, source item, and line number for an error, but it does not show the method, event handler, constructor, destructor, or property accessor that contains the error. In a window or class with several members, a row such as Window1 Line 2 is ambiguous when the user is not already looking at the relevant code view.

Expected behaviour: diagnostics inside members should include the containing member or event context, for example Window1.Test Line 1 or equivalent wording such as Window1 method Test line 1. Diagnostics outside a member should keep the existing source item and line display.