more stack slightly improved debugging

rust/src/plant_hal.rs

@@ -621,6 +621,7 @@ impl PlantCtrlBoardInteraction for PlantCtrlBoard<'_> {
                 qos: AtLeastOnce,
                 retain: true,
             }),
+            client_id: Some("plantctrl"),
             keep_alive_interval : Some(Duration::from_secs(60*60*2)),
             //room for improvement
             ..Default::default()