Improve error handling, ensure robust defaults, and eliminate unsafe unwraps/expectations across modules.

Software/MainBoard/rust/src/hal/water.rs

@@ -33,7 +33,8 @@ impl<'a> TankSensor<'a> {
         one_wire_pin.apply_output_config(&OutputConfig::default().with_pull(Pull::None));
 
         let mut adc1_config = AdcConfig::new();
-        let tank_pin = adc1_config.enable_pin_with_cal::<_, AdcCalLine<_>>(gpio5, Attenuation::_11dB);
+        let tank_pin =
+            adc1_config.enable_pin_with_cal::<_, AdcCalLine<_>>(gpio5, Attenuation::_11dB);
         let tank_channel = Adc::new(adc1, adc1_config);
 
         let one_wire_bus = OneWire::new(one_wire_pin, false);
@@ -141,12 +142,17 @@ impl<'a> TankSensor<'a> {
             let value = self.tank_channel.read_oneshot(&mut self.tank_pin);
             //force yield
             Timer::after_millis(10).await;
-            *sample = value.unwrap();
+            match value {
+                Ok(v) => *sample = v,
+                Err(e) => {
+                    bail!("ADC Hardware error: {:?}", e);
+                }
+            };
         }
         self.tank_power.set_low();
 
         store.sort();
         let median_mv = store[TANK_MULTI_SAMPLE / 2] as f32;
-        Ok(median_mv/1000.0)
+        Ok(median_mv / 1000.0)
     }
 }