fix(input): /菜单上下键滚动抖动与高亮条偶发闪烁

- 修复 rAF 第一帧 now 早于 startTime 导致 scrollTop 反向抖动
- 过滤动画结束后的延迟 scroll 事件，避免误进入 manualScrolled 模式导致高亮条闪一下消失

static/src/components/input/InputComposer.vue

@@ -597,6 +597,11 @@ const slashHighlightTop = ref(4);
 /** 手动滚动后切到鼠标 hover 模式，隐藏 JS 高亮条 */
 const slashManualScrolled = ref(false);
 let slashAnimId: number | null = null;
+/** 动画真正进行中（比 animId 更可靠，可覆盖 rAF 结束后的延迟 scroll 事件） */
+let slashAnimating = false;
+/** 记录最近一次动画的目标 scrollTop 和结束时间，用于过滤动画后的延迟 scroll 事件 */
+let lastSlashAnimatedScroll: number | null = null;
+let lastSlashAnimationEndTime = 0;
 
 const slashHighlightStyle = computed(() => {
   if (slashManualScrolled.value) return { display: 'none' };
@@ -615,6 +620,8 @@ const animateSlash = (element: HTMLElement, targetScroll: number) => {
   if (interrupted) {
     cancelAnimationFrame(slashAnimId);
   }
+  slashAnimating = true;
+  lastSlashAnimatedScroll = targetScroll;
   const startScroll = element.scrollTop;
   const startHighlight = slashHighlightTop.value;
   const distScroll = targetScroll - startScroll;
@@ -624,7 +631,8 @@ const animateSlash = (element: HTMLElement, targetScroll: number) => {
   const startTime = performance.now();
 
   const step = (now: number) => {
-    const elapsed = now - startTime;
+    // rAF 第一帧的 now 偶尔会早于 startTime，导致 progress 为负、scrollTop 反向抖动
+    const elapsed = Math.max(0, now - startTime);
     const progress = Math.min(elapsed / duration, 1);
     const eased = 1 - Math.pow(1 - progress, 3);
     element.scrollTop = startScroll + distScroll * eased;
@@ -633,6 +641,8 @@ const animateSlash = (element: HTMLElement, targetScroll: number) => {
       slashAnimId = requestAnimationFrame(step);
     } else {
       slashAnimId = null;
+      slashAnimating = false;
+      lastSlashAnimationEndTime = performance.now();
     }
   };
   slashAnimId = requestAnimationFrame(step);
@@ -640,7 +650,18 @@ const animateSlash = (element: HTMLElement, targetScroll: number) => {
 
 /** 手动滚动时切到鼠标 hover 模式，不再跟踪键盘选中 */
 const onSlashScroll = () => {
-  if (slashAnimId !== null) return;
+  if (slashAnimating || slashAnimId !== null) return;
+  const list = skillSlashList.value;
+  if (!list) return;
+  const now = performance.now();
+  // 动画结束后的延迟 scroll 事件：scrollTop 与动画目标一致，说明是动画尾声，忽略
+  if (
+    lastSlashAnimatedScroll !== null &&
+    now - lastSlashAnimationEndTime < 150 &&
+    Math.abs(list.scrollTop - lastSlashAnimatedScroll) < 1
+  ) {
+    return;
+  }
   slashManualScrolled.value = true;
 };
 
@@ -766,6 +787,9 @@ const closeSlashMenu = () => {
     cancelAnimationFrame(slashAnimId);
     slashAnimId = null;
   }
+  slashAnimating = false;
+  lastSlashAnimatedScroll = null;
+  lastSlashAnimationEndTime = 0;
   skillSlashOpen.value = false;
   skillSlashQuery.value = '';
   skillSlashActiveIndex.value = 0;