What is the workflow for debugging node-clangd code?

To investigate https://github.com/clangd/vscode-clangd/issues/396, I'd like to step through some code in node-clangd in the debugger. However, I'm not clear on how to do this:

* If I start debugging in a vscode-clangd workspace, I don't have access to node-clangd source files to set a breakpoint in.
* If I start debugging in a node-clangd workspace, trying to set a breakpoint doesn't succeed (the breakpoint isn't "bound").

What is the proper way to do this? My apologies if this should be obvious, I'm not well versed in node or vscode extension development.