Add array length guard in TimeframesFilter timeFrameData computed

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

src/components/Discover/Map/Filter/TimeframesFilter.vue

@@ -135,6 +135,8 @@ const sliderData = computed(() => {
 
 // Add the minimum and maximum values
 const timeFrameData = computed(() => {
+  if (!filterTimeframe.value?.data || filterTimeframe.value.data.length < 10)
+    return [];
   const data = filterTimeframe.value.data.map((i) => ({ x: i.x, y: i.y }));
   // See ./public/timeFrameSlope for the y-axis slope calculation diagram
   // x values are 0 ~ 11,