Open the "add torrent" dialog when clicking a magnet link instead of adding the torrent directly with default settings

[malte-v]

Hi! First off, I'd like to thank you for making this awesome tool. It works very reliably!
Now, I have a little suggestion concerning the UI flow when adding a torrent from a magnet link: Currently, the torrent is just added with the default settings, so it is not possible to change the download directory, for example. I think it would be better if clicking a magnet link would result in the "add torrent from magnet link" dialog being opened, with the magnet link already filled in. That would allow the user to make adjustments before adding the torrent.