Fix chart data issues: 24-hour format, Y-axis bounds, rounding modes

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

src/module/setChartData.js

@@ -58,6 +58,7 @@ export function setLineChartData(baseData, xMax, xMin, isPercent, yMax, yMin) {
  * @returns {number} The extrapolated and clamped Y minimum value.
  */
 function calculateYMin(baseData, isPercent, yMin, yMax) {
+  if (baseData.length < 2) return yMin;
   let a = 0;
   let c = 1;
   let d = baseData[0].y;
@@ -77,6 +78,7 @@ function calculateYMin(baseData, isPercent, yMin, yMax) {
  * @returns {number} The extrapolated and clamped Y maximum value.
  */
 function calculateYMax(baseData, isPercent, yMin, yMax) {
+  if (baseData.length < 10) return yMax;
   let ma = 9;
   let mb = baseData[8].y;
   let mc = 10;
@@ -119,12 +121,12 @@ function clampValue(value, isPercent, min, max) {
  * @param {Array<{x: string, y: number}>} baseData - The data points from
  *   the backend with ISO timestamp x values.
  * @returns {Array<{x: string, y: number}>} Data with x values formatted
- *   as "YYYY/M/D hh:mm:ss".
+ *   as "YYYY/M/D HH:mm:ss".
  */
 export function setBarChartData(baseData) {
   let data = baseData.map((i) => {
     return {
-      x: getMoment(i.x).format("YYYY/M/D hh:mm:ss"),
+      x: getMoment(i.x).format("YYYY/M/D HH:mm:ss"),
       y: i.y,
     };
   });