phase-1: optimize code

tests/EtfScorer.test.js

@@ -29,3 +29,26 @@ test('audit breakdown includes cost, yield, vol keys', () => {
   assert(result.audit.breakdown.yield != null);
   assert(result.audit.breakdown.vol != null);
 });
+
+test('penalises ETF with volume below liquidity floor', () => {
+  const result = EtfScorer.score({ expenseRatio: 0.03, yield: 2.0, volume: 100000 }, rules);
+  assert(result.audit.breakdown.vol < 0, 'low-volume ETF should receive negative vol score');
+});
+
+test('scores 5Y return when threshold configured', () => {
+  const rulesWithReturn = {
+    ...rules,
+    weights: { ...rules.weights, fiveYearReturn: 2 },
+    thresholds: { ...rules.thresholds, minFiveYearReturn: 8.0 },
+  };
+  const good = EtfScorer.score(
+    { expenseRatio: 0.03, yield: 2.0, volume: 1000000, fiveYearReturn: 10 },
+    rulesWithReturn,
+  );
+  const poor = EtfScorer.score(
+    { expenseRatio: 0.03, yield: 2.0, volume: 1000000, fiveYearReturn: 5 },
+    rulesWithReturn,
+  );
+  assert(good.audit.breakdown.fiveYearReturn > 0, 'strong 5Y return should score positively');
+  assert(poor.audit.breakdown.fiveYearReturn < 0, 'weak 5Y return should score negatively');
+});