Feedback sent on another canvas now gets its own draft

When you send feedback about Obeya from another canvas, Obeya turns it into a draft wish. Until now, if an older feedback draft was still open, the dialog showed that old draft unchanged. The new wish only appeared in one easy-to-miss line below it, so it looked as if your feedback had been lost. Now an old draft that has only a title is replaced straight away, and the new draft is written from your feedback. An old draft with text or screenshots is kept, but the top of the dialog shows the feedback the new draft will be written from, with a button to discard the old draft, and opening the old one on GitHub no longer drops the waiting wish.