refactor: PlantInfo structure (consistent layout)

- fix: use tagged enum serialization for MoistureSensorError and PumpError
- fix: flatten PlantInfo sensors to SensorTelemetry with top-level moisture_pct

Software/MainBoard/rust/src/plant_state.rs

@@ -1,5 +1,6 @@
 use crate::hal::Moistures;
 use crate::{config::PlantConfig, hal::HAL, in_time_range};
+use alloc::string::String;
 use chrono::{DateTime, TimeDelta, Utc};
 use chrono_tz::Tz;
 use serde::{Deserialize, Serialize};
@@ -7,12 +8,14 @@ use serde::{Deserialize, Serialize};
 const MOIST_SENSOR_MAX_FREQUENCY: f32 = 70000.; // 70kHz
 const MOIST_SENSOR_MIN_FREQUENCY: f32 = 400.; // this is really, really dry, think like cactus levels
 
-#[derive(Debug, PartialEq, Serialize)]
+#[derive(Debug, PartialEq, Clone, Serialize)]
+#[serde(tag = "kind")]
 pub enum MoistureSensorError {
     MissingMessage,
     NotExpectedMessage { hz: f32 },
     ShortCircuit { hz: f32, max: f32 },
     OpenLoop { hz: f32, min: f32 },
+    BoardError { message: String },
 }
 
 #[derive(Debug, PartialEq, Serialize)]
@@ -46,6 +49,14 @@ impl MoistureSensorState {
 impl MoistureSensorState {}
 
 #[derive(Debug, PartialEq, Serialize)]
+pub struct SensorTelemetry {
+    pub moisture_pct: Option<f32>,
+    pub raw_hz: Option<f32>,
+    pub error: Option<MoistureSensorError>,
+}
+
+#[derive(Debug, PartialEq, Serialize)]
+#[serde(tag = "kind")]
 pub enum PumpError {
     PumpNotWorking {
         failed_attempts: usize,
@@ -215,7 +226,7 @@ impl PlantState {
     pub fn plant_moisture(
         &self,
     ) -> (
-        Option<u8>,
+        Option<f32>,
         (Option<&MoistureSensorError>, Option<&MoistureSensorError>),
     ) {
         match (
@@ -223,13 +234,13 @@ impl PlantState {
             self.sensor_b.moisture_percent(),
         ) {
             (Some(moisture_a), Some(moisture_b)) => {
-                (Some(((moisture_a + moisture_b) / 2.) as u8), (None, None))
+                (Some((moisture_a + moisture_b) / 2.), (None, None))
             }
             (Some(moisture_percent), _) => {
-                (Some(moisture_percent as u8), (None, self.sensor_b.is_err()))
+                (Some(moisture_percent), (None, self.sensor_b.is_err()))
             }
             (_, Some(moisture_percent)) => {
-                (Some(moisture_percent as u8), (self.sensor_a.is_err(), None))
+                (Some(moisture_percent), (self.sensor_a.is_err(), None))
             }
             _ => (None, (self.sensor_a.is_err(), self.sensor_b.is_err())),
         }
@@ -247,7 +258,7 @@ impl PlantState {
                 if let Some(moisture_percent) = moisture_percent {
                     if self.pump_in_timeout(plant_conf, current_time) {
                         false
-                    } else if moisture_percent < plant_conf.target_moisture {
+                    } else if moisture_percent < plant_conf.target_moisture.into() {
                         in_time_range(
                             current_time,
                             plant_conf.pump_hour_start,
@@ -273,19 +284,21 @@ impl PlantState {
         &self,
         plant_conf: &PlantConfig,
         current_time: &DateTime<Tz>,
-    ) -> PlantInfo<'_> {
+    ) -> PlantInfo {
+        let (moisture_pct, _) = self.plant_moisture();
         PlantInfo {
-            sensor_a: &self.sensor_a,
+            moisture_pct,
-            sensor_b: &self.sensor_b,
+            sensor_a: Self::sensor_to_telemetry(&self.sensor_a),
+            sensor_b: Self::sensor_to_telemetry(&self.sensor_b),
             mode: plant_conf.mode,
             do_water: self.needs_to_be_watered(plant_conf, current_time),
-            dry: if let Some(moisture_percent) = self.plant_moisture().0 {
+            dry: if let Some(moisture_percent) = moisture_pct {
-                moisture_percent < plant_conf.target_moisture
+                moisture_percent < plant_conf.target_moisture.into()
             } else {
                 false
             },
             cooldown: self.pump_in_timeout(plant_conf, current_time),
-            out_of_work_hour: in_time_range(
+            out_of_work_hour: !in_time_range(
                 current_time,
                 plant_conf.pump_hour_start,
                 plant_conf.pump_hour_end,
@@ -315,15 +328,42 @@ impl PlantState {
             last_fertilizer_time: self.last_fertilizer_time,
         }
     }
+
+    fn sensor_to_telemetry(sensor: &MoistureSensorState) -> SensorTelemetry {
+        match sensor {
+            MoistureSensorState::NoMessage => {
+                SensorTelemetry {
+                    moisture_pct: None,
+                    raw_hz: None,
+                    error: None
+                }
+            }
+            MoistureSensorState::MoistureValue {
+                hz,
+                moisture_percent,
+            } => SensorTelemetry {
+                moisture_pct: Some(*moisture_percent),
+                raw_hz: Some(*hz),
+                error: None,
+            },
+            MoistureSensorState::SensorError(err) => SensorTelemetry {
+                moisture_pct: None,
+                raw_hz: None,
+                error: Some(err.clone()),
+            },
+        }
+    }
 }
 
 #[derive(Debug, PartialEq, Serialize)]
 /// State of a single plant to be tracked
-pub struct PlantInfo<'a> {
+pub struct PlantInfo {
+    /// combined plant moisture from available sensors
+    moisture_pct: Option<f32>,
     /// state of humidity sensor on bank a
-    sensor_a: &'a MoistureSensorState,
+    sensor_a: SensorTelemetry,
     /// state of humidity sensor on bank b
-    sensor_b: &'a MoistureSensorState,
+    sensor_b: SensorTelemetry,
     /// configured plant watering mode
     mode: PlantWateringMode,
     /// the plant needs to be watered