The OG card for a pull says its check verdict and who shipped it #2047

Part of #455 (split). /og/pull/:ref reads like a change summary.

Done:

• [ ] The card shows the pull's state (open, merged, closed), the latest check verdict (green, red, running, none), the author, and who merged it and when, if it has been merged.
• [ ] The ETag changes when the check verdict changes.
• [ ] Tests cover an open pull with a red check, a merged pull and a pull with no check.

Files: src/web/pages/og.ts, test/og-route.test.ts. Read pulls through the existing getters only; do not edit src/core/pulls.ts (steward hold until #2037 and #2017 land). Risk: the check verdict must come from data that is already public on the pull page.

Parked by the crew: the check failed ("two forges in one process keep their own error and refusal signals") and the decider saw no point in another try (pull #2241 closed). Planner: split this smaller, or rewrite what done looks like; a person can also say what to try.

Closed: already done on main in ea64226c (pull #2241).