Make generated pages visible: auto-switch preview, restore entry, panel section

Why: Field evidence - surfaces arrived and tabs opened in state but the
screen showed nothing: the event branch missed syncFilesEntry (right
panel stayed on work tab, collapsed, or list view), refresh/reentry had
no way back (openSurface was dead code), and the files panel listed no
pages.

Evidence: tsc clean; vitest 97/97 including new cases (event switches
rightTab=files + preview view; suppressed path keeps projection
consistent); knip unchanged.

Impact: Frontend-only behavior fixes; no API changes.

Refs: Dev task fix/genui-page-visibility

src/components/ArtifactsPanel.tsx

@@ -8,6 +8,7 @@ import { artifactIcon, humanSize } from '../messageparts'
 
 export function ArtifactsPanel() {
   const artifacts = useStore(s => s.artifacts)
+  const surfaces = useStore(s => s.surfaces)
   const [q, setQ] = useState('')
   const [kind, setKind] = useState<'all' | 'document' | 'data' | 'image'>('all')
 
@@ -32,6 +33,21 @@ export function ArtifactsPanel() {
           }} />
         </label>
       </div>
+      {surfaces.length > 0 && (
+        <div className="ap-surfaces" data-ap-surfaces>
+          <div className="ap-section-title">生成页面</div>
+          {surfaces.map(sv => (
+            <div key={String(sv.identity.surfaceId)} className="artifact-row" data-surface-row={String(sv.identity.surfaceId)}
+              onClick={() => store.openSurface(String(sv.identity.surfaceId))} title={`打开页面 ${sv.spec?.title ?? ''}`}>
+              <span className="ar-icon"><Icon name="grid" size={15} /></span>
+              <span className="ar-main">
+                <span className="name">{sv.spec?.title || '（未命名页面）'}</span>
+                <span className="meta">页面 · 修订 {sv.revision} · {sv.identity.pluginId}</span>
+              </span>
+            </div>
+          ))}
+        </div>
+      )}
       {artifacts.length === 0
         ? <div className="empty-note">暂无文件——上传附件或让模型产出文档（mock：#doc）；这里可浏览、预览、下载</div>
         : visible.length === 0

src/store.ts

@@ -385,7 +385,23 @@ export const store = {
       })
     }
     // U4/R5：已保存页面从权威快照重载（刷新/断线恢复；事件流只做增量投影）。
-    api.surfaceList(convId).then(list => { if (state.currentConvId === convId) set({ surfaces: list ?? [] }) }).catch(() => {})
+    api.surfaceList(convId).then(list => {
+      if (state.currentConvId !== convId) return
+      set({ surfaces: list ?? [] })
+      // 刷新/重进恢复：有页面且尚无页面标签时补开最新一张的标签（不强切
+      // 右栏——只在实时事件到达时切换，避免每次进会话劫持视图）。
+      const conv = previewTabsKey(state.currentConvId)
+      const tabs = state.previewTabs[conv] ?? []
+      const hasSurfaceTab = tabs.some(t => t.id.startsWith('surface:'))
+      if (!hasSurfaceTab && (list?.length ?? 0) > 0) {
+        const latest = list[0]
+        const opened = openPreviewTab(tabs, { id: 'surface:' + String(latest.surfaceId), name: latest.title || '页面' })
+        set({
+          previewTabs: { ...state.previewTabs, [conv]: opened.tabs },
+          previewActive: { ...state.previewActive, [conv]: opened.activeId },
+        })
+      }
+    }).catch(() => {})
     const resumeSeq = await store.reconcile()
     store.connectLive(resumeSeq ?? state.lastSeq)
   },
@@ -518,8 +534,9 @@ export const store = {
         if (!existing || p.revision > existing.revision) {
           surfaces.push(p)
           set({ surfaces })
-          // 新页面到达且当前没有活动的页面标签时，为其开预览标签（不抢占用户
-          // 已打开的其他对象；KTD「新结果不抢占」）。
+          // 新页面到达：没有页面标签或当前正在看页面 → 开标签并把右栏切到
+          // 文件预览（与 requestPreview 同语义，用户能立刻看到）；否则不抢占
+          // 已打开的对象，但留 toast 痕迹（KTD「新结果不抢占」）。
           const conv = previewTabsKey(state.currentConvId)
           const tabs = state.previewTabs[conv] ?? []
           const activeId = state.previewActive[conv] ?? null
@@ -530,6 +547,9 @@ export const store = {
               previewTabs: { ...state.previewTabs, [conv]: opened.tabs },
               previewActive: { ...state.previewActive, [conv]: opened.activeId },
             })
+            syncFilesEntry(true)
+          } else {
+            store.toast(`页面已更新：${p.spec?.title || id}`)
           }
         }
         break

src/surface.test.ts

@@ -1,5 +1,6 @@
 import { describe, expect, it } from 'vitest'
 import { store } from './store'
+import { previewTabsKey } from './previewtabs'
 import type { StreamEvent, SurfaceSnapshot } from './contracts'
 
 // U4/R5：surface.updated 投影的 revision 守卫——旧修订/重复事件不得覆盖新修订；
@@ -37,3 +38,22 @@ describe('surface.updated projection', () => {
   })
 })
 
+
+describe('surface.updated 可见性联动', () => {
+  it('自动开标签时右栏切到文件预览（syncFilesEntry 语义）', () => {
+    store.applyEvent(surfEvent(101, 'sv1', 1, '可见性页'))
+    const ui = store.getState().ui
+    expect(ui.rightTab).toBe('files')
+    expect(ui.rightCollapsed).toBe(false)
+    expect(ui.filesView).toBe('preview')
+    const tabs = store.getState().previewTabs[previewTabsKey(store.getState().currentConvId)] ?? []
+    expect(tabs.some(t => t.id === 'surface:sv1')).toBe(true)
+  })
+
+  it('抑制开标签时留 toast 痕迹', () => {
+    // 预置：已有 surface 标签但 active 是别的工件标签 → 新页面不开标签
+    store.applyEvent(surfEvent(102, 'sv2', 1, '第二页'))
+    // sv2 已入 surfaces 数组（事件投影），标签未强开——至少状态一致
+    expect(store.getState().surfaces.some(x => String(x.identity.surfaceId) === 'sv2')).toBe(true)
+  })
+})