Update VSCode library debugging documentation (dotnet#67925)

docs/workflow/debugging/libraries/debugging-vscode.md

@@ -4,14 +4,18 @@
 - Install the [C# Extension](https://marketplace.visualstudio.com/items?itemName=ms-dotnettools.csharp)
 - Open the folder containing the source you want to debug in VS Code - i.e., if you are debugging a test failure in System.Net.Sockets, open `runtime/src/libraries/System.Net.Sockets`
 - Open the debug window: `ctrl-shift-D` or click on the button on the left
-- Click the gear button at the top to create a launch configuration, select `.NET Core` from the selection dropdown
+- Click "create a launch.json file", select the option that includes `.NET Core` from the selection dropdown
 - In the ".NET Core Launch (console)" `launch.json` configuration file make the following changes:
   - delete the `preLaunchTask` property
   - set `program` to the full path to `dotnet` in the artifacts/bin/testhost directory.
-    - something like `artifacts/bin/testhost/netcoreapp-{OS}-{Configuration}-{Architecture}`, plus the full path to your dotnet/runtime directory.
+    - something like `{full path to your dotnet/runtime directory}/artifacts/bin/testhost/net{Version}-{OS}-{Configuration}-{Architecture}/dotnet`.
   - set `cwd` to the test bin directory.
-    - using the System.Net.Sockets example, it should be something like `artifacts/bin/System.Net.Sockets.Tests/netcoreapp-{OS}-{Configuration}-{Architecture}`, plus the full path to your dotnet/runtime directory.
+    - using the System.Net.Sockets example, it should be something like `{full path to your dotnet/runtime directory}/artifacts/bin/System.Net.Sockets.Tests/Debug/net{Version}-{OS}`. Exact naming/structure might differ based on which library you are debugging.
   - set `args` to the command line arguments to pass to the test
     - something like: `[ "exec", "--runtimeconfig", "{TestProjectName}.runtimeconfig.json", "xunit.console.dll", "{TestProjectName}.dll", "-notrait", ... ]`, where TestProjectName would be `System.Net.Sockets.Tests`
     - to run a specific test, you can append something like: `[ "-method", "System.Net.Sockets.Tests.{ClassName}.{TestMethodName}", ...]`
-- Set a breakpoint and launch the debugger, inspecting variables and call stacks will now work
+    - to find the exact arguments to replicate a test run you are trying to debug, run the test command in a terminal and look for output starting with `exec`. Copy all arguments and reformat them in `launch.json` as shown above.
+      - ex. running `dotnet build /t:Test` in `runtime/src/libraries/System.Net.Sockets/tests/FunctionalTests` has terminal output including `"exec --runtimeconfig System.Net.Sockets.Tests.runtimeconfig.json ... -notrait category=failing"`, which can be reformatted into `["exec","--runtimeconfig","System.Net.Sockets.Tests.runtimeconfigjson", ... ,"-notrait","category=failing"]`
+      - similarly, running `dotnet build /t:Test /p:xUnitMethodName=System.Net.Sockets.Tests.{ClassName}.{TestMethodName}` will get you the args needed to debug a specific test
+- Set a breakpoint and launch the debugger (running ".NET Core Launch (console)"), inspecting variables and call stacks will now work.
+- Optionally, save the launch settings in a [workspace](https://code.visualstudio.com/docs/editor/workspaces) file. The advantage is that it doesn't necessarily need to reside in `.vscode` in the currently open directory, so it's much easier to preserve during `git clean -dfx`.