Add support for magnet links

- Parse magnets links
- Get the trackers for it and communicate with the peers to get the infoHash details for the torrent files
- Communicate with the peers as usual, there isn't much change in the implementation.
- If no trackers are available, Do DHT (This needs a big change, don't implement it just yet)

The issue names no files, tests, or entry points. Start by locating the existing torrent-file parsing, tracker communication, and peer communication flows; define completion around parsing magnet links and retrieving the infoHash through trackers, while leaving DHT support out of scope.

Written by the indexing model from the issue text.