fix(core): 测试清单 行24/28-39/46 — 流水线脚本&资产/消息页 + 单镜重跑后端接口

前端流水线(pipeline.tsx):脚本助手三选项指引(AI全生/一句话/自带脚本)+来源风格推荐;
风格/人物设定卡并持久化到 project.metadata;Enter发送/Shift+Enter换行;长文折叠10行;
生成进度流提示;分镜人物/场景标签可编辑并持久化+点击添加分镜;单镜重跑/删除即时反馈;
脚本助手记录按项目 localStorage 持久化;Stage2 基础资产补替换/重跑/可编辑提示词;
三视图采用弹窗+缺三视图气泡。
消息页(messages):复用全站 .search-inline 搜索框、去掉小标题背景方块。
视频项目(projects):列表按创建时间倒序,新建置顶。
性能:action 改后台 hydrate,消除创建/确认后白等(行29/37)。

后端(projects/ai):新增单镜 AI 重跑接口 POST /projects/{id}/rerun-script-segment/
(regenerate_script_segment 服务,复用 AITask+计费 reserve/charge/release;+2 单测)。

前端 build 通过;后端 check 0/无新迁移/apps.projects 14 测试通过。

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

core/backend/apps/projects/views.py

@@ -18,6 +18,7 @@ from apps.ai.services import (
     generate_project_script,
     generate_storyboard_frame,
     poll_video_segment,
+    regenerate_script_segment,
     submit_storyboard,
     submit_video_segment,
     synthesize_project_voiceover,
@@ -216,6 +217,28 @@ class ProjectViewSet(TeamScopedViewSetMixin, ModelViewSet):
             segment.save(update_fields=[*changed, "updated_at"])
         return Response(ScriptVersionSerializer(segment.script_version).data)
 
+    @action(detail=True, methods=["post"], url_path="rerun-script-segment")
+    def rerun_script_segment(self, request, pk=None):
+        """单条分镜 AI 重跑:只重新生成该 ScriptSegment 的旁白+画面提示(其它镜不动),按现有计费扣费。"""
+        project = self.get_object()
+        segment_id = request.data.get("segment_id")
+        if not segment_id:
+            return Response({"detail": "segment_id is required"}, status=status.HTTP_400_BAD_REQUEST)
+        try:
+            segment = ScriptSegment.objects.get(id=segment_id, script_version__project=project)
+        except ScriptSegment.DoesNotExist:
+            return Response({"detail": "script segment not found"}, status=status.HTTP_404_NOT_FOUND)
+        try:
+            script = regenerate_script_segment(
+                project=project,
+                user=request.user,
+                segment=segment,
+                instruction=str(request.data.get("instruction") or "").strip(),
+            )
+        except ValueError as exc:
+            return Response({"detail": str(exc)}, status=status.HTTP_400_BAD_REQUEST)
+        return Response(ScriptVersionSerializer(script).data)
+
     @action(detail=True, methods=["post"], url_path="add-script-segment")
     @transaction.atomic
     def add_script_segment(self, request, pk=None):