LinXiv v0.4.0; paper manager now using n0's iroh for P2P collaboration

LinXiv is an open-source academic paper manager that uses n0's iroh library to enable peer-to-peer collaboration between users. Version 0.4.0 introduces iroh-based P2P networking for sharing and syncing paper collections without a central server. The project is hosted on GitHub and targets researchers and developers managing academic literature.