What the heck is /pkg?

A mysterious `/pkg` directory has appeared in macOS 27.0 with a path entry `/pkg/env/global/bin` added to the system PATH, but its purpose remains unclear. The directory contains subdirectories (env, etc, inv, var) and was added to the Data volume in macOS 26.4 before appearing in the Signed System Volume in version 27.0, leading to speculation it could be related to a potential first-party package management system, though Apple has provided no official explanation.