fix: 加固日历日期与动态错误合同（09-05-error-explainability-payment-readiness，09-08-reimbursement-payment-closeout）

server/tests/unit/routes/workflow.batch.test.js

@@ -196,6 +196,37 @@ async function buildApp(options = {}) {
 }
 
 describe("workflow batch routes", () => {
+  it("returns the precise reminder cooldown time without creating another reminder", async () => {
+    const taskId = "11111111-1111-4111-8111-111111111111";
+    const { app, tx, state } = await buildApp({
+      actor: { id: OWNER_ID, roleCodes: ["employee"], permissionCodes: [] },
+    });
+    tx.workflowHistory.findFirst = vi.fn().mockResolvedValue({
+      id: "synthetic-reminder", created_at: new Date("2026-09-16T08:30:00.000Z"),
+    });
+    vi.useFakeTimers({ toFake: ["Date"] });
+    vi.setSystemTime(new Date("2026-09-16T09:30:00.000Z"));
+    try {
+      const response = await app.inject({ method: "POST", url: `/api/workflow/tasks/${taskId}/remind`, payload: {} });
+      expect(response.statusCode).toBe(409);
+      expect(response.json().error).toMatchObject({ code: "VALID_001", details: {
+        reasonCode: "workflow.remind_cooldown", workflow: "remind_too_frequent",
+        nextAllowedAt: "2026-09-17T08:30:00.000Z",
+      } });
+      expect(tx.workflowHistory.findFirst).toHaveBeenCalledWith(expect.objectContaining({ where: {
+        task_id: taskId, actor_id: OWNER_ID, action: "remind",
+        created_at: { gte: new Date("2026-09-15T09:30:00.000Z") },
+      } }));
+      expect(tx.workflowHistory.create).not.toHaveBeenCalled();
+      expect(tx.notification.create).not.toHaveBeenCalled();
+      expect(tx.workflowTask.update).not.toHaveBeenCalled();
+      expect(state.history).toEqual([]);
+    } finally {
+      vi.useRealTimers();
+      await app.close();
+    }
+  });
+
   it.each([
     ["POST", "/workflow/tasks/invalid/approve", {}, "workflow.task_id_invalid"],
     ["POST", "/workflow/tasks/11111111-1111-4111-8111-111111111111/reject", { comment: " " }, "workflow.comment_invalid"],