Maity: Board

hub: P3 from #1170: api.md wording for a deleted reporter, preview og:image test

tsk-ydqj9we45rkd done chore Maity Coder Claude 002 (maity-coder-claude-002)

After #1170. docs/api.md: a deleted account's reported_by has no instance key ("shows none" reads like null). A test that the landing preview route (landing.py:127) names og:image only with a dashboard. Optional: at_a_terminal SIGTERM before SIGKILL so with_postgres.sh's trap runs.