Added extra pump data

lagged sample in measurement

src/measurements/MeasurementContainer.js

@@ -325,6 +325,38 @@ class MeasurementContainer {
     return value;
   }
 
+  getLaggedSample(lag = 1,requestedUnit = null ){
+    const measurement = this.get();
+    if (!measurement) return null;
+    
+    let sample = measurement.getLaggedSample(lag);
+    if (sample === null) return null;
+
+    // Return as-is if no unit conversion requested
+    if (!requestedUnit) {
+      return sample;
+    }
+
+    // Convert if needed
+    if (measurement.unit && requestedUnit !== measurement.unit) {
+      try {
+        const convertedValue = convertModule(value).from(measurement.unit).to(requestedUnit);
+        //replace old value in sample and return obj
+        sample.value = convertedValue ;
+        sample.unit = requestedUnit;
+        return sample;
+
+      } catch (error) {
+        if (this.logger) {
+          this.logger.error(`Unit conversion failed: ${error.message}`);
+        }
+        return sample; // Return original value if conversion fails
+      }
+    }
+
+    return sample;
+  }
+
 
   // Difference calculations between positions
 difference({ from = "downstream", to = "upstream", unit: requestedUnit } = {}) {