⚡ perf(vscode): 代码阅读预览发给页面的块带内容指纹：扩展端按卡片内容、在源码里占的地方连同子块的指纹算摘要，页面按指纹认出没变的块沿用原来的对象，不再逐块深比内容，5126 行的文档到了比对 10.6ms → 0.4ms

vscode/webview-ui/src/codeReader/App.tsx

@@ -22,7 +22,7 @@ import { createPageStore } from './pageState'
 import { NO_PLACEMENT, placementOf } from './placement'
 import { chatOf, PATH_ASK_ANCHOR, sameChat } from './qa'
 import { TextMarksContext } from './SegmentText'
-import { shareUnchanged } from './sharing'
+import { shareBlocks, shareUnchanged } from './sharing'
 import { StickyLines } from './StickyLines'
 import { createStore, useStore } from './store'
 import { useChangeNav } from './useChangeNav'
@@ -151,8 +151,8 @@ export function App(): ReactElement | null {
         case 'document': {
           const restoring = restoreCall.current
           restoreCall.current = undefined
-          // 和上一份内容一样的块还是原来的对象：没变的卡片不重画
-          const next = shareUnchanged(page.get().doc, msg)
+          // 指纹没变的块还是原来的对象：没变的卡片不重画
+          const next = { ...msg, blocks: shareBlocks(page.get().doc?.blocks, msg.blocks) }
           const reopened = restoring && openingCall(next, restoring.anchor, restoring.entry)
           marks.set(current => ({ ...current, names: nameMap(msg.names), placement: placementOf(next.blocks) }))
           page.update(current => ({