Function project_hash_from_root 

pub fn project_hash_from_root(project_root: &str) -> String

Calculate project_hash from project_root using SHA256

This function canonicalizes the path before hashing to ensure consistency across symlinks and different path representations. For example, /var/folders/... and /private/var/folders/... will produce the same hash on macOS where /var is a symlink to /private/var.