feat: tune multi-source peak sensitivity

tests/unit/evaluation.test.js

@@ -86,6 +86,32 @@ test("복수 source와 threshold detection을 one-to-one matching한다", () =>
   );
 });
 
+test("peak 검출 감도를 낮추면 약한 두 번째 음원을 선택한다", () => {
+  const scan = { xMin: -2, xMax: 2, yMin: -2, yMax: 2, z: 1, columns: 5, rows: 5 };
+  const rawMap = new Float32Array(25);
+  rawMap[6] = 10;
+  rawMap[18] = 2.5;
+  const options = {
+    rawMap,
+    scan,
+    sources: [
+      { id: "strong", position: [-1, 1, 1] },
+      { id: "weak", position: [1, -1, 1] },
+    ],
+    matchToleranceM: 0.25,
+    minimumPeakDistanceM: 0,
+  };
+
+  const conservative = evaluateDasBand({ ...options, detectionThresholdRatio: 0.5 });
+  const recommended = evaluateDasBand({ ...options, detectionThresholdRatio: 0.25 });
+
+  assertEqual(conservative.detections.length, 1, "50% threshold omits the weak peak");
+  assertEqual(conservative.counts.falseNegative, 1, "one source remains undetected");
+  assertEqual(recommended.detections.length, 2, "25% threshold retains the weak peak");
+  assertEqual(recommended.counts.truePositive, 2, "both sources match at recommended sensitivity");
+  assertEqual(recommended.parameters.detectionThresholdRatio, 0.25, "selected ratio is recorded");
+});
+
 test("zero map 평가가 빈 peak와 유한한 metric을 반환한다", () => {
   const scan = { xMin: -1, xMax: 1, yMin: -1, yMax: 1, z: 1, columns: 2, rows: 2 };
   const evaluation = evaluateDasBand({