You can access data from deleted forks, deleted repositories and even private repositories on GitHub. And it is available forever. This is known by GitHub, and intentionally designed that way.
Why would you need to control these through a mailing list? The maintainers should have accounts (I don’t see the point in federating maintainers instead of just discussion, especially when this is self-hostable), and only those with permissions should be setting up labels, assignees, inline reviews, and CI. And yes, sourcehut has a UI for this, though alternatives through email commands are also available.
And no, I do not see the point of reactions. If you really need a vote, use a voting service.
Why would you need to control these through a mailing list? The maintainers should have accounts (I don’t see the point in federating maintainers instead of just discussion, especially when this is self-hostable), and only those with permissions should be setting up labels, assignees, inline reviews, and CI. And yes, sourcehut has a UI for this, though alternatives through email commands are also available.
And no, I do not see the point of reactions. If you really need a vote, use a voting service.