New: CustomFormat Score for history grabs

Fixes #5892
Fixes #5893

frontend/src/Utilities/Number/formatCustomFormatScore.js

@@ -0,0 +1,16 @@
+
+function formatCustomFormatScore(input) {
+  const score = Number(input);
+
+  if (score > 0) {
+    return `+${score}`;
+  }
+
+  if (score < 0) {
+    return score;
+  }
+
+  return '';
+}
+
+export default formatCustomFormatScore;