Fix getYTicksByIndex truncating integers by using toFixed

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/module/timeLabel.js

@@ -76,11 +76,7 @@ const getTimeUnitAndValueToUse = (secondToDecide) => {
  * @returns {string} The formatted tick label (e.g. "2.5h").
  */
 export function getYTicksByIndex(stepSize, index, unitToUse) {
-  const rawStepsizeMultIndex = (stepSize * index).toString();
-  const shortenStepsizeMultIndex = rawStepsizeMultIndex.substring(
-    0,
-    rawStepsizeMultIndex.indexOf(".") + 1 + TOFIXED_DECIMAL,
-  );
+  const shortenStepsizeMultIndex = (stepSize * index).toFixed(TOFIXED_DECIMAL);
   return `${shortenStepsizeMultIndex}${unitToUse}`;
 }
 

tests/unit/module/timeLabel.test.js

@@ -123,7 +123,7 @@ describe("getStepSizeOfYTicks", () => {
 
 describe("getYTicksByIndex", () => {
   it("formats tick label with unit", () => {
-    expect(getYTicksByIndex(2, 3, "h")).toBe("6h");
+    expect(getYTicksByIndex(2, 3, "h")).toBe("6.0h");
   });
 
   it("truncates to 1 decimal place", () => {