I've been having fun with the s&box game engine by Face Punch
While there have been many improvements things are still somewhat immature and there isn't much documentation on how to get things working as you want for your dev environment so I'm documenting it here.
Then in VSCode, specifically open the code folder, not the project folder
so for me my path is ~\repos\sandbox-farming-game\code where sandbox-farming-game is my project folder
Hope this helps. It will probably break in future but good luck.