maintenance: add tags

For packaging Python libraries, it's more convenient to use the original repos instead of Pypi artifacts, cuz the latter often lack tests (and Gephipy is no exception), but without tags in the repo it's impossible to set up update hooks that detect new version when it comes out.

Start by inspecting the repository's current packaging and release setup, then compare the version information in the repository with the PyPI artifact. Determine which tags the update hooks should detect and how they should be created. Done means the repository has a clear, repeatable tagging process that exposes new versions to those hooks.

Written by the indexing model from the issue text.