⚡ perf(vscode): 代码阅读预览的卡片位置量过就记着，内容或大小变了才重量：粘性标题、记滚动位置、上报可见行、跳转按顶层块二分找，滚动时不再每帧量全部卡片，滚动回调里也不读会逼排版的位置

vscode/webview-ui/src/codeReader/useChangeNav.ts

@@ -2,9 +2,8 @@ import type { ChangeStop } from './diffView'
 import type { StickyScrollSettings } from './types'
 import { useCallback, useLayoutEffect, useRef, useState } from 'react'
 import { nextStop } from './diffView'
-import { anchorAt } from './scrollPosition'
+import { pageLayout } from './pageLayout'
 import { flash } from './useReveal'
-import { measureBlocks, pinnedHeight } from './useScrollPosition'
 import { stickyInset } from './useStickyScroll'
 
 /** 跳到的那处离筛选栏下沿留多少像素。 */
@@ -33,7 +32,7 @@ export function useChangeNav(stops: readonly ChangeStop[], collapsed: ReadonlySe
     }
     const card = document.querySelector<HTMLElement>(`.cr-block[data-id="${target.id}"]`)
     if (card) {
-      window.scrollTo(0, card.getBoundingClientRect().top + window.scrollY - pinnedHeight() - stickyInset(card, sticky) - MARGIN)
+      window.scrollTo(0, card.getBoundingClientRect().top + window.scrollY - pageLayout.pinnedHeight() - stickyInset(card, sticky) - MARGIN)
       flash(card)
     }
     jumped.current = { id: target.id, scrollY: window.scrollY }
@@ -45,7 +44,7 @@ export function useChangeNav(stops: readonly ChangeStop[], collapsed: ReadonlySe
       return
     const from = jumped.current && Math.abs(window.scrollY - jumped.current.scrollY) < 2 ? jumped.current.id : undefined
     const index = from === undefined ? -1 : stops.findIndex(stop => stop.id === from)
-    const at = index >= 0 ? { index } : { line: anchorAt(measureBlocks(), window.scrollY + pinnedHeight())?.line }
+    const at = index >= 0 ? { index } : { line: pageLayout.anchorAt(window.scrollY + pageLayout.pinnedHeight())?.line }
     setTarget(stops[nextStop(stops, at, step)])
   }, [stops])