jpsync: a git-like CLI to safely sync local folders with a remote JupyterHub

jpsync (jp) is a zero-dependency, pure-Python command-line tool that keeps a local folder in sync with a directory on a remote JupyterHub, the way git keeps a working copy in sync with a remote. It is designed for research workflows on shared GPU clusters: edit notebooks and scripts locally, push them up, run on the server, and pull results back, without ever silently overwriting or deleting remote files on a multi-user machine.