Fix division by zero

apps/api/src/app/portfolio/calculator/portfolio-calculator.ts

@@ -713,9 +713,13 @@ export abstract class PortfolioCalculator {
           netPerformanceWithCurrencyEffect:
             netPerformanceWithCurrencyEffectSinceStartDate,
           netPerformanceInPercentage:
-            netPerformanceSinceStartDate / timeWeightedInvestmentValue,
+            timeWeightedInvestmentValue === 0
+              ? 0
+              : netPerformanceSinceStartDate / timeWeightedInvestmentValue,
           netPerformanceInPercentageWithCurrencyEffect:
-            netPerformanceWithCurrencyEffectSinceStartDate /
+            timeWeightedInvestmentValue === 0
+              ? 0
+              : netPerformanceWithCurrencyEffectSinceStartDate /
                 timeWeightedInvestmentValue,
           // TODO: Add net worth with valuables
           // netWorth: totalCurrentValueWithCurrencyEffect