probalby found most of the import related stuff, now the real refactor begins

rust/src/plant_state.rs

@@ -3,6 +3,7 @@ use crate::{
     hal::{Sensor, HAL},
     in_time_range,
 };
+use alloc::string::String;
 use chrono::{DateTime, TimeDelta, Utc};
 use chrono_tz::Tz;
 use serde::{Deserialize, Serialize};