update:
Ok, I made sure the tests work on all three (3) configurations (native, new wow64, old wow64). In that process I discovered `CreateToolhelp32Snapshot` wasn't working on old wow64 when targeting a wow process, so I fixed that. Also on native `CreateToolhelp32Snapshot` may [spuriously return `ERROR_BAD_LENGTH`](https://learn.microsoft.com/en-us/windows/win32/api/tlhelp32/nf-tlhelp32-cre...), so I added handling for that as well.