Verify remote render recovery identity and endpoint binding

tests/routes/video-canvas-smart-edit.test.ts

@@ -169,3 +169,51 @@ test("SRT input rejects bad time ranges and preserves multiline unicode text", (
   const rows = parseSrt("\uFEFF1\r\n00:00:01,000 --> 00:00:02,500\r\n你好\r\n第二行");
   expect(rows[0]).toEqual({ start: SECOND, end: 2.5 * SECOND, text: "你好\n第二行" });
 });
+
+test("remote render records deterministic identity before network failure and refuses endpoint changes", async () => {
+  const { remoteRender } = await import("@/lib/video-canvas/smart-edit/remote-render");
+  const savedURL = process.env.SMART_EDIT_RENDER_URL,
+    savedToken = process.env.SMART_EDIT_RENDER_TOKEN,
+    oldFetch = globalThis.fetch;
+  process.env.SMART_EDIT_RENDER_URL = "http://127.0.0.1:19399";
+  process.env.SMART_EDIT_RENDER_TOKEN = "x".repeat(64);
+  const checkpoints: any[] = [];
+  let calls = 0;
+  globalThis.fetch = (async () => {
+    calls++;
+    return new Response("{}", { status: 503 });
+  }) as typeof fetch;
+  try {
+    const lifecycle = {
+      active: async () => {},
+      save: async (value: unknown) => {
+        checkpoints.push(value);
+      },
+    };
+    await expect(remoteRender(plan(), "user", "stable-task", "/unused", lifecycle)).rejects.toThrow(
+      "任务已保存",
+    );
+    await expect(
+      remoteRender(plan(), "user", "stable-task", "/unused", {
+        ...lifecycle,
+        resume: checkpoints[0],
+      }),
+    ).rejects.toThrow("任务已保存");
+    expect(checkpoints[0]).toEqual(checkpoints[1]);
+    expect(calls).toBe(2);
+    process.env.SMART_EDIT_RENDER_URL = "http://127.0.0.1:19400";
+    await expect(
+      remoteRender(plan(), "user", "stable-task", "/unused", {
+        ...lifecycle,
+        resume: checkpoints[0],
+      }),
+    ).rejects.toThrow("所属服务器已变化");
+    expect(calls).toBe(2);
+  } finally {
+    globalThis.fetch = oldFetch;
+    if (savedURL === undefined) delete process.env.SMART_EDIT_RENDER_URL;
+    else process.env.SMART_EDIT_RENDER_URL = savedURL;
+    if (savedToken === undefined) delete process.env.SMART_EDIT_RENDER_TOKEN;
+    else process.env.SMART_EDIT_RENDER_TOKEN = savedToken;
+  }
+});