fix(assets,storyboard): 统一素材库 entity 口径、修复远端空结果遮蔽，补分镜输出契约与解析 (#510)

远端空页只在本地仍有未同步结果或本页全是 entity 时回退，避免把合法空搜索铺成过期缓存。

Co-authored-by: Cursor <cursoragent@cursor.com>

web/test/canvas-storyboard-rows-parse.test.ts

@@ -0,0 +1,57 @@
+import { describe, expect, test } from "bun:test";
+
+import { storyboardRowsFromTask } from "../src/lib/canvas/canvas-project-domain";
+import type { GenerationTask } from "../src/services/api/task-center";
+
+function storyboardTask(resultJson: string): GenerationTask {
+    return { id: "task-1", resultJson } as GenerationTask;
+}
+
+// 后端 canvas_text 任务统一落 {mode, reasoning, text} 包装，模型输出正文嵌在 text 里；
+// 分镜解析必须穿透包装取内层 {title, rows}，同时兼容模板路径直接落顶层的结构。
+describe("storyboardRowsFromTask", () => {
+    test("从 {mode, reasoning, text} 包装的 text 内层解析分镜行", () => {
+        const payload = { title: "桃源三结义", rows: [
+            { shotNumber: 1, durationSeconds: 8, plotDescription: "朝堂开篇", dialogue: "", characters: ["刘备"], mustHave: ["列队"], optionalDetails: [] },
+            { shotNumber: 2, durationSeconds: 10, plotDescription: "告示墙前叹气", dialogue: "唉……", characters: ["刘备", "关羽"] },
+        ] };
+        const task = storyboardTask(JSON.stringify({ mode: "text", reasoning: "思考过程", text: JSON.stringify(payload) }));
+        const result = storyboardRowsFromTask(task);
+        expect(result.title).toBe("桃源三结义");
+        expect(result.rows).toHaveLength(2);
+        expect(result.rows[0].shotNumber).toBe(1);
+        expect(result.rows[0].status).toBe("idle");
+        expect(result.rows[0].characters).toEqual(["刘备"]);
+        expect(result.rows[1].characters).toEqual(["刘备", "关羽"]);
+    });
+
+    test("text 内层被 ```json 代码块包裹时仍可解析", () => {
+        const payload = { title: "章节", rows: [{ shotNumber: 1, plotDescription: "单镜头" }] };
+        const wrappedText = "```json\n" + JSON.stringify(payload) + "\n```";
+        const task = storyboardTask(JSON.stringify({ mode: "text", text: wrappedText }));
+        expect(storyboardRowsFromTask(task).rows).toHaveLength(1);
+    });
+
+    test("text 内层混入解释文字时按首尾大括号截取解析", () => {
+        const payload = { title: "章节", rows: [{ shotNumber: 1, plotDescription: "单镜头" }] };
+        const noisyText = "以下是分镜表：\n" + JSON.stringify(payload) + "\n如需调整请告知。";
+        const task = storyboardTask(JSON.stringify({ mode: "text", text: noisyText }));
+        expect(storyboardRowsFromTask(task).rows).toHaveLength(1);
+    });
+
+    test("兼容顶层直接落 {title, rows} 的结构", () => {
+        const task = storyboardTask(JSON.stringify({ title: "章节", rows: [{ shotNumber: 1, plotDescription: "单镜头" }] }));
+        expect(storyboardRowsFromTask(task).rows).toHaveLength(1);
+    });
+
+    test("text 内层不是 JSON 时抛出缺行错误", () => {
+        // 无契约时期模型返回 Markdown 表格的真实场景。
+        const task = storyboardTask(JSON.stringify({ mode: "text", text: "| 7-41 | 全景/拉远 | 桃园结义 |" }));
+        expect(() => storyboardRowsFromTask(task)).toThrow("分镜任务没有返回镜头行");
+    });
+
+    test("rows 为空数组时抛出缺行错误", () => {
+        const task = storyboardTask(JSON.stringify({ mode: "text", text: JSON.stringify({ title: "空", rows: [] }) }));
+        expect(() => storyboardRowsFromTask(task)).toThrow("分镜任务没有返回镜头行");
+    });
+});