Windows support discussion

[StefanStojanovic]

Hello, everyone. I was brought to this page by this comment on one of my PRs in the Node.js repo, as it was said that the change from there could be a problem for llnode. Later, I tried installing llnode from npm and building it from the source code but failed with both. Upon further investigation I found the other users faced the same issue, which was caused by the change in node-gyp some time ago. I've seen this discussion in node-gyp, but it didn't move past that.

Since this is my first time looking into llnode, I'll write the conclusions to which I came, that may or may not be true, but they should be a good starting point for discussion:

1. llnode hasn't been working on Windows for some time (node-gyp change that broke it landed in 2018, issue opened in 2019).
2. Changes in node-gyp are required to get it to work on Windows again (or a workaround)
3. Prohibiting setting ClangCL as PlatformToolset in project file from node-gyp should not affect llnode as it is already generating a .vcxproj file without it on Windows, and then using options to set CLToolTool/Path when building

Refs: nodejs/node#55784
Refs: #321
Refs: nodejs/node-gyp#1164
Refs: nodejs/node-gyp#3072

[joyeecheung]

I have not been helping out with the maintenance of this repo for some time so it might not be accurate, but at least 1 and 3 look correct to me. Not quite sure about 2 since I am not very familiar with node-gyp on Windows in general.