Update precompilation to use the library manager instead of relative

paths.

This website is written to assume that $pwd is always in the functional
tests directory when it's launched. This works fine for the functional
tests, but causes issues in many other contexts, including VS.
I'll update the comment. The issue is more that we have **no guarantee** what the base path is pointing to. As we found with recent vs builds, new scenarios where we need this code to run can pop up at any time :laughing: