feat: introduce MeasureBackedCursor record

Author: metacosm

measure/src/main/java/net/laprun/sustainability/power/measure/MeasureBackedCursor.java

@@ -0,0 +1,13 @@
+package net.laprun.sustainability.power.measure;
+
+import net.laprun.sustainability.power.analysis.Recorder;
+
+public record MeasureBackedCursor(Recorder measure, PartialCursor cursor) {
+    public double sum() {
+        return cursor.sum(measure.liveMeasures());
+    }
+
+    public double[] view() {
+        return cursor.viewOf(measure.liveMeasures());
+    }
+}