Handovers no longer fail for a missing demo page

After Obeya restarted, agents working on a repository that shares demos on the personal site could get stuck: every handover was refused because the demo page was missing, even though the agent had sent its title and text. The agents had resumed before GitHub confirmed that the repository is public, so the page they sent was dropped. Obeya now asks for the page only where the agent's tools accept one. If such a demo is shared later, Obeya writes the page text itself.