Foresight — signed Flatpak repo

Automatic updates for Foresight, the rsync front-end that previews every change before a byte moves.

flatpak install --user https://superuser-miguel.github.io/foresight-repo/foresight.flatpakref
flatpak run io.github.superuser_miguel.Foresight

Updates then arrive with flatpak update. Signed with the project's GPG key.