Wire up MODE_PROBLEMS_ALERTING in query routing

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

pkg/datasource/datasource.go

@@ -150,6 +150,8 @@ func (ds *ZabbixDatasource) QueryData(ctx context.Context, req *backend.QueryDat
 					frames, queryErr = zabbixDS.queryItemIdData(queryCtx, &query)
 				case MODE_PROBLEMS:
 					queryErr = backend.DownstreamError(test) //send a test error
+				case MODE_PROBLEMS_ALERTING:
+					frames, queryErr = zabbixDS.queryProblemsAlerting(queryCtx, &query)
 				default:
 					queryErr = backend.DownstreamError(ErrNonMetricQueryNotSupported)
 				}