fix(ai-character): 폼 도메인 검증 복구

src/features/audio-contents/tests/audio-form-create-red.test.tsx

@@ -191,6 +191,29 @@ test("AudioContentFormPage reveals preview duration offset inputs only when prev
   });
 });
 
+test("AudioContentFormPage rejects malformed preview offsets through the submit button", async () => {
+  // Given
+  const uploadedBodies: XMLHttpRequestBodyInit[] = [];
+  renderCreateForm(uploadedBodies);
+  await fillRequiredCreateFields();
+  fireEvent.change(screen.getByLabelText("가격"), { target: { value: "1" } });
+  fireEvent.click(screen.getByLabelText("미리듣기 생성"));
+  const previewStart = screen.getByLabelText("미리듣기 시작");
+  const previewEnd = screen.getByLabelText("미리듣기 종료");
+
+  // When
+  fireEvent.change(previewStart, { target: { value: "30" } });
+  fireEvent.change(previewEnd, { target: { value: "01:00" } });
+  fireEvent.click(screen.getByRole("button", { name: "생성" }));
+
+  // Then
+  expect(await screen.findAllByText("미리듣기 시간은 HH:MM:SS 형식으로 입력하세요.")).toHaveLength(2);
+  expect(previewStart).toHaveAttribute("aria-invalid", "true");
+  expect(previewEnd).toHaveAttribute("aria-invalid", "true");
+  await waitFor(() => expect(previewStart).toHaveFocus());
+  expect(uploadedBodies).toHaveLength(0);
+});
+
 test("AudioContentFormPage conditionally renders and clears the native scheduled release datetime", async () => {
   // Given
   renderCreateForm();