사이드바 접기 기능 추가

devfront/src/components/layout/AppLayout.test.tsx

@@ -116,6 +116,24 @@ describe("devfront AppLayout", () => {
     expect(document.documentElement.classList.contains("light")).toBe(true);
   });
 
+  it("toggles the sidebar and persists the collapsed state", async () => {
+    const container = await renderLayout();
+
+    const collapseButton = container.querySelector(
+      'button[aria-label="Collapse sidebar"]',
+    ) as HTMLButtonElement;
+    await act(async () => {
+      collapseButton.click();
+    });
+
+    expect(window.localStorage.getItem("baron_shell_sidebar_collapsed")).toBe(
+      "true",
+    );
+    expect(
+      container.querySelector('button[aria-label="Expand sidebar"]'),
+    ).not.toBeNull();
+  });
+
   it("toggles profile menu, navigates to profile, toggles theme, and logs out", async () => {
     const container = await renderLayout();