Unify git status PR info into a single `pr` field

- Replace `openPr`/`mergedPr` with `pr` in server and contracts
- Add PR `state` (`open`/`closed`/`merged`) to git status schema
- Resolve latest branch PR via `gh pr list --state all` sorted by `updatedAt`
973e62373eJulius Marminge committed on 2/16/2026, 3:46:24 AMparentdcdb9ac
5 files changedLine totals unavailable