Add a function to find xrefs to a method or a field

Add a function to find xrefs to a method or a field in the menu when you right click on it

No files or tests are named. Start by locating the right-click menu entry point for methods and fields and any existing cross-reference search, then establish the expected results for both menu actions. Done means the action is available from each relevant context menu and finds the requested method or field references.

Written by the indexing model from the issue text.