Fix phantom UNKNOWN slice caused by floating-point rounding

libs/ui/src/lib/portfolio-proportion-chart/portfolio-proportion-chart.component.ts

@@ -204,8 +204,9 @@ export class GfPortfolioProportionChartComponent
 
       const unknownValueInPercentage = new Big(1).minus(totalValueInPercentage);
 
-      if (unknownValueInPercentage.gt(0)) {
-        // If total is below 100%, allocate the remaining percentage to UNKNOWN_KEY
+      // If total is below 100%, allocate the remaining percentage to UNKNOWN_KEY,
+      // but ignore negligible remainders to avoid a phantom slice
+      if (unknownValueInPercentage.gt(0.0001)) {
         if (chartData[UNKNOWN_KEY]) {
           chartData[UNKNOWN_KEY].value = chartData[UNKNOWN_KEY].value.plus(
             unknownValueInPercentage