Judge a pull request's head merged into its trunk, and name the trunk commit

A check judged the head alone, so two pull requests that each passed could
break the trunk together (node-engine #66 on 2026-10-09), and a recheck after
the trunk moved judged the same head again. The build seat now merges the head
into the trunk's head in its own clone, never pushed, fails a head that does not
merge cleanly naming the files, and the verdict names the head, the trunk
commit and the commits read beside it, for the forge and mesh-delivery to weigh
against the trunk's next move (novox/hq ADR 0323, issue 341).

cmd/mesh-controller/delivery.go

@@ -1185,7 +1185,7 @@ func askGroupCheck(ctx context.Context, open *stores, group string, members []or
 			return "", fmt.Errorf("%s cannot be cloned for the group's check: %w", m.ID, err)
 		}
 		request.Check.Members = append(request.Check.Members, link.GroupMember{Owner: mp.Owner, Repo: mp.Repo,
-			Number: mp.Number, Repository: url, Ref: mp.Commit, Paths: mp.Paths})
+			Number: mp.Number, Repository: url, Ref: mp.Commit, Paths: mp.Paths, Base: mp.Base})
 	}
 	seat := buildSeatHeld(ctx)
 	ask, err := askOverOn(seat)