Open processed source versions through the existing preview

Why: Source context must remain attached to the bytes being read.

Evidence: SELF frontend tests and production build pass.

Impact: Carries an optional expected hash and preserves one preview location.

Refs: fast-slow-u2-u3 Task 5 source-version acceptance

src/components/PreviewPane.tsx

@@ -24,6 +24,7 @@ export function PreviewPane() {
       })
     : undefined
   const art = active ? artifacts.find(a => a.id === active.id) : undefined
+  const contentUrl=art?api.artifactContentUrl(art.id)+(active?.sourceContext?.expectedHash?`?expectedHash=${encodeURIComponent(active.sourceContext.expectedHash)}`:''):''
   const textKind = !!art && isTextKind(art)
   const [content, setContent] = useState<string | null>(null)
   const [editing, setEditing] = useState(false)
@@ -35,12 +36,12 @@ export function PreviewPane() {
     setContent(null)
     if (!art || !isTextKind(art)) return
     let cancelled = false
-    fetch(api.artifactContentUrl(art.id))
-      .then(r => r.text())
+    fetch(contentUrl)
+      .then(r => {if(!r.ok)throw new Error('source unavailable');return r.text()})
       .then(text => { if (!cancelled) setContent(text) })
       .catch(() => { if (!cancelled) setContent('（读取失败）') })
     return () => { cancelled = true }
-  }, [art?.id])
+  }, [art?.id,contentUrl])
 
   if (!active) return null
   if (active.id.startsWith('surface:')) {
@@ -120,7 +121,7 @@ export function PreviewPane() {
             id: art.id,
             name: art.name,
             mime: art.mime,
-            contentUrl: api.artifactContentUrl(art.id),
+            contentUrl,
             downloadUrl: api.artifactDownloadUrl(art.id),
           }} />
         ) : <div className="empty-note" style={{ padding: 14 }}>这个文件已不在当前项目里</div>}

src/components/Workbench.tsx

@@ -19,7 +19,7 @@ export const docBridge: DocBridge = {
     try{const out=await api.taskSource(cardId,source.id)
       if(context!==store.getState().currentConvId||project!==store.getState().currentProjectId)return
       if(!out.artifact){store.toast('来源当前不可用，正在核实工作记录');if(context)void store.refreshCards(context);return}
-      store.requestTaskSourcePreview(out.artifact,{notice:out.versionState==='changed'?'当前文件已更新；下方引用来自任务处理时的版本，不能作为当前文件的结论':'当前文件与处理时来源一致；下方是本项发现引用的片段',quote:out.source.quote??''})
+      store.requestTaskSourcePreview(out.artifact,{notice:out.versionState==='changed'?'当前文件已更新；下方引用来自任务处理时的版本，不能作为当前文件的结论':'任务处理时引用的来源版本；下方是本项发现引用的片段',quote:out.source.quote??'',expectedHash:out.versionState==='current'?out.source.contentHash:undefined})
       if(out.versionState==='changed'&&context)void store.refreshCards(context)
     }catch{if(context===store.getState().currentConvId&&project===store.getState().currentProjectId){store.toast('来源当前无法读取，正在核实工作记录');if(context)void store.refreshCards(context)}}
   },

src/previewtabs.ts

@@ -3,7 +3,7 @@
 export interface PreviewTab {
   id: string
   name: string
-  sourceContext?: {notice:string;quote:string}
+  sourceContext?: {notice:string;quote:string;expectedHash?:string}
 }
 
 export function openPreviewTab(tabs: PreviewTab[], tab: PreviewTab): { tabs: PreviewTab[]; activeId: string } {

src/store.ts

@@ -1255,7 +1255,7 @@ export const store = {
    * 工件预览唯一入口：在第三栏「文件」入口打开或激活标签（多文件多标签）。
    * 打开第一张自动切到预览子视图；关掉最后一张回到文件列表，并收回展开态。
    */
-  requestTaskSourcePreview(a:Artifact,sourceContext:{notice:string;quote:string}){
+  requestTaskSourcePreview(a:Artifact,sourceContext:{notice:string;quote:string;expectedHash?:string}){
     store.requestPreview(a)
     const conv=previewTabsKey(state.currentConvId)
     set({previewTabs:{...state.previewTabs,[conv]:(state.previewTabs[conv]??[]).map(tab=>tab.id===a.id?{...tab,sourceContext}:tab)}})