Act on multiple issues at once

[diamond-lizard]

It would be very useful if forge could act on multiple issues at once.

The workflow I envision is marking a number of issues (either at once by something like a forge-mark-issues-in-region function, or one at a time) and then on those marked issues with some other function, like forge-edit-topic-labels or perhaps (un)assign all those issues to GitHub project(s).

This would be useful to me since I often create a bunch of issues for myself as todo lists, and then want to assign those issues to a GitHub project. Doing this through the GitHub web gui is slow and cumbersome. Being able to do this through forge would be great.

The ability to, for instance, close many issues at once would also be great.