✨ feat(vscode): 代码阅读预览里工作区外的库文件也能问 AI，问答记进第一个工作区文件夹，重写注释不对库文件开放

vscode/webview-ui/src/codeReader/qa.test.ts

@@ -10,7 +10,7 @@ function thread(anchor: string, ...ids: string[]): QaThreadView {
 }
 
 function message(threads: QaThreadView[], current: QaMessage['current'] = []): QaMessage {
-  return { type: 'qa', available: true, threads, path: [], subject: 'file', current, rewrites: [], rewriteCurrent: [] }
+  return { type: 'qa', available: true, rewritable: true, threads, path: [], subject: 'file', current, rewrites: [], rewriteCurrent: [] }
 }
 
 function qa(threads: QaThreadView[], current: QaMessage['current'] = []): QaAction {
@@ -53,6 +53,7 @@ describe('问 AI 的状态', () => {
       message: {
         type: 'qa',
         available: true,
+        rewritable: true,
         threads: [],
         path: [{ id: 'p', question: '这文件夹干什么', answer: '放源码', createdAt: '2026-09-25T10:00:00.000Z' }],
         subject: 'folder',