[upstream_utils] Can't run on Windows

[WispySparks]

Upstream utils scripts can't be run on windows due to many paths having hardcoded /. Could be fixed by replacing these with os.path.join or os.path.sep.

[Gold856]

This is a problem for only a select few scripts that have direct comparisons between raw paths specified by hand, like ./imgui.h and paths created with os.path.join. The two paths will have inconsistencies in terms of slashes, and the comparisons will therefore fail (because they don't match). One solution is to use os.path.join as a kind of "input sanitizer", and preprocess all manually specified paths with os.path.join before passing them to functions.

[auscompgeek]

It'd be worth fixing these scripts to use pathlib instead.

[calcmogul]

Although pathlib doesn't add pathlib.Path.walk() (an equivalent of os.walk()) until Python 3.12, and we support down to Python 3.9 at the moment. We may have to shim it.

[TheTripleV]

Path(top).glob("**/*") give you all the files

[auscompgeek]

os.walk() accepts path-like objects, so it shouldn't be too bad either way.