⚡ 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/useReveal.ts

@@ -2,9 +2,8 @@ import type { ScrollPosition } from './occurrences'
 import type { DocumentMessage, Reveal } from './types'
 import { useLayoutEffect } from 'react'
 import { blockPath } from './filter'
+import { pageLayout } from './pageLayout'
 import { revealPlan, scrollTopToShow, uncoveredPlan } from './reveal'
-import { blockForLine } from './scrollPosition'
-import { measureBlocks, pinnedHeight } from './useScrollPosition'
 import { stickyHeight } from './useStickyScroll'
 
 /** 让一块或属性表里的一行闪几下（codeReader.css 的 [data-flash]）；正在闪的同一处再跳一次时从头闪。 */
@@ -28,7 +27,7 @@ export function flash(el: HTMLElement): void {
 /** 把 el 滚进钉住的筛选栏和卡片下面的视口。已经整个看得见就不滚。beforeScroll 在真正滚动前拿到将要落到的位置。 */
 export function showInViewport(el: HTMLElement, beforeScroll?: (position: ScrollPosition) => void): void {
   const rect = el.getBoundingClientRect()
-  const pinned = pinnedHeight() + stickyHeight()
+  const pinned = pageLayout.pinnedHeight() + stickyHeight()
   const top = scrollTopToShow(
     { top: rect.top + window.scrollY, bottom: rect.bottom + window.scrollY },
     window.scrollY,
@@ -75,9 +74,9 @@ export function useReveal(
     if (!doc || !reveal)
       return
     if (reveal.definition === undefined) {
-      const top = blockForLine(measureBlocks(), reveal.line)?.top
+      const top = pageLayout.cardForLine(reveal.line)?.top
       if (top !== undefined)
-        window.scrollTo(0, top - pinnedHeight())
+        window.scrollTo(0, top - pageLayout.pinnedHeight())
       done()
       return
     }