Please clarify the copyright license

Currently there appears to be no copyright license on this repo. Given that the author has thusfar declined to pursue actions against any of the forks (or Go reimplementations) of this code, I assume/hope that "all rights reserved" is not intentional.

The issue names no file, test, or entry point, and asks for clarification rather than specifying a documentation change. First inspect the repository for existing licensing metadata and seek the author's decision; done means the copyright license status is explicitly recorded in the repository.

Written by the indexing model from the issue text.