fix(coordinator): scan owner_id in UIReadRepo.ListJobs

jobColumns gained owner_id but ListJobs' Scan still read 12 targets,
so the query returned 13 columns and pgx failed at runtime. Only the
integration tests (real DB) caught it; memstore-backed unit tests did not.

coordinator/internal/storage/postgres/ui_read_repo.go

@@ -44,6 +44,7 @@ func (r *UIReadRepo) ListJobs(ctx context.Context, limit int) ([]domain.Job, err
 		if err := rows.Scan(
 			&j.ID, &j.Workload, &j.InputURI, &j.Parameters, &status, &j.CreatedAt, &j.CompletedAt,
 			&j.InputArtifactID, &j.ResultArtifactID, &j.ErrorCode, &j.ErrorMessage, &j.ReducerStartedAt,
+			&j.OwnerID,
 		); err != nil {
 			return nil, err
 		}