Launch VS Code from WSL Bash
The Creators update did install the interop functionality. However, it seems you need to install realpath in WSL in order for the path to be recognized. I'm not sure why this is the case but running sudo apt-get install realpath fixed it for me!
EDIT: After updating to the Fall Creators Update launching VSCode from WSL works out of the box ð
You could always create an alias in the WSL Bash shell
alias code="/mnt/c/Program\ Files/Microsoft\ VS\ Code/Code.exe"
If you add this to your .bashrc or .zshrc file then it will always be available when you start a new instance of your environment.