refactor(core): 脚本收口——只留 agent 出稿,删旧散文路 + 单镜重跑改走 agent

删 /generate-script/ 端点 + generate_project_script + build_script_prompt + 旧单镜 build_segment_rerun_prompt;前端删静默兜底(agent 失败明确报错,不再掉回旧路)+ onGenerateScript prop/api。rerun-script-segment 改用 agent 单镜逻辑(regenerate_segment_via_agent:读全脚本上下文/保留其余镜/落新版本)。根因:旧路不产 script_entities/entity_refs,下游故事板/视频参考图断线→图飘。测试:删 3 个旧 generate 用例 + 重写 rerun 为 agent 版,ai+projects 23 测试除 4 个既有 base-asset 失败外全绿。

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

core/frontend/src/routes/pipeline.tsx

@@ -422,9 +422,7 @@ export function PipelinePage(props: {
   avatarChar: string;
   logout: () => void;
   scriptModelName: string;
-  textModels?: ModelConfig[];
-  onGenerateScript: (prompt: string, source?: string) => Promise<unknown>;
-  onAdoptScript: (scriptId: string) => void | Promise<unknown>;
+  textModels?: ModelConfig[];  onAdoptScript: (scriptId: string) => void | Promise<unknown>;
   onUpdateShot: (payload: { segment_id: string; narration?: string; visual_prompt?: string; duration_seconds?: number }) => Promise<unknown>;
   onAddShot: (afterSegmentId: string) => Promise<unknown>;
   onDeleteShot: (segmentId: string) => Promise<unknown>;
@@ -460,7 +458,7 @@ export function PipelinePage(props: {
 }) {
   const {
     project, loading, navigate, user, team, products, projects, assets, billing, notice, unreadCount, avatarChar, logout,
-    scriptModelName, textModels, onGenerateScript, onAdoptScript, onUpdateShot, onAddShot, onDeleteShot, onRerunShot, onSaveProjectMeta, onAdoptVideoVersion, onGenerateVoiceover,
+    scriptModelName, textModels, onAdoptScript, onUpdateShot, onAddShot, onDeleteShot, onRerunShot, onSaveProjectMeta, onAdoptVideoVersion, onGenerateVoiceover,
     onGenerateBaseAsset, onAdoptBaseAsset, onAttachBaseAsset, onGenerateActor, onUploadActor, onGenerateTriview, onRenameActor, onGenerateStoryboard, onSkipStoryboard,
     onSubmitVideo, onSubmitAllVideos, onPollVideosQuiet, exportResult, onRefreshExport, onRefreshProject,
     onUploadVideoSegment, onUploadBgm, onSaveTimeline, onSubmitExport
@@ -929,9 +927,8 @@ export function PipelinePage(props: {
       if (ok) {
         // 已收到 saved:流其实成功了(只是收尾抖动),绝不回退重发,避免重复生成+重复扣费
       } else if (!receivedEvent) {
-        // 一个事件都没收到 = 流式根本没跑起来(网关不支持 SSE)→ 退回旧同步端点
-        const res = await onGenerateScript(prompt, source ?? chatMode).catch(() => null);
-        ok = !!res;
+        // 流式没跑起来:明确报错,不再静默退回旧散文路(旧路不产 script_entities,会让下游故事板/视频参考图断线)
+        pushMsg("ai", "脚本生成没能启动(流式连接失败),请重试。");
       } else {
         // 流中途断了(后端已通过 finally 释放预扣额度):不重试,提示用户
         pushMsg("ai", "生成中断了,请重试。");