fix(ui): repair router_settings tests broken by full antd mock

The antd mocks in RouterSettingsForm.test.tsx and index.test.tsx
replaced the entire antd module with only Select, so the Switch and
Button used by nested components failed to render. Use importOriginal
to preserve the rest of antd and override only Select.

Also fix the TagFilteringToggle click assertion — antd's Switch fires
onChange with (checked, event), so toHaveBeenCalledWith(true) was
always going to miss. Assert the checked arg directly instead of
coupling to antd's call signature.

ui/litellm-dashboard/src/components/router_settings/RouterSettingsForm.test.tsx

@@ -4,25 +4,30 @@ import userEvent from "@testing-library/user-event";
 import RouterSettingsForm from "./RouterSettingsForm";
 import type { RouterSettingsFormValue } from "./RouterSettingsForm";
 
-// Use the same antd mock as RoutingStrategySelector to keep things consistent
-vi.mock("antd", () => ({
-  Select: Object.assign(
-    ({ value, onChange, children }: any) => (
-      <select
-        data-testid="strategy-select"
-        value={value ?? ""}
-        onChange={(e) => onChange(e.target.value)}
-      >
-        {children}
-      </select>
-    ),
-    {
-      Option: ({ value, children }: any) => (
-        <option value={value}>{children}</option>
+// Override antd Select (complex to drive in JSDOM) while preserving the rest
+// of antd (Switch, Button, etc.) so nested components render normally.
+vi.mock("antd", async (importOriginal) => {
+  const actual = await importOriginal<typeof import("antd")>();
+  return {
+    ...actual,
+    Select: Object.assign(
+      ({ value, onChange, children }: any) => (
+        <select
+          data-testid="strategy-select"
+          value={value ?? ""}
+          onChange={(e) => onChange(e.target.value)}
+        >
+          {children}
+        </select>
       ),
-    }
-  ),
-}));
+      {
+        Option: ({ value, children }: any) => (
+          <option value={value}>{children}</option>
+        ),
+      }
+    ),
+  };
+});
 
 const defaultValue: RouterSettingsFormValue = {
   routerSettings: {},

ui/litellm-dashboard/src/components/router_settings/TagFilteringToggle.test.tsx

@@ -90,6 +90,7 @@ describe("TagFilteringToggle", () => {
 
     await user.click(screen.getByRole("switch"));
 
-    expect(onToggle).toHaveBeenCalledWith(true);
+    expect(onToggle).toHaveBeenCalledTimes(1);
+    expect(onToggle.mock.calls[0][0]).toBe(true);
   });
 });

ui/litellm-dashboard/src/components/router_settings/index.test.tsx

@@ -3,24 +3,28 @@ import { renderWithProviders, screen, waitFor } from "../../../tests/test-utils"
 import userEvent from "@testing-library/user-event";
 import RouterSettings from "./index";
 
-vi.mock("antd", () => ({
-  Select: Object.assign(
-    ({ value, onChange, children }: any) => (
-      <select
-        data-testid="strategy-select"
-        value={value ?? ""}
-        onChange={(e) => onChange(e.target.value)}
-      >
-        {children}
-      </select>
-    ),
-    {
-      Option: ({ value, children }: any) => (
-        <option value={value}>{children}</option>
+vi.mock("antd", async (importOriginal) => {
+  const actual = await importOriginal<typeof import("antd")>();
+  return {
+    ...actual,
+    Select: Object.assign(
+      ({ value, onChange, children }: any) => (
+        <select
+          data-testid="strategy-select"
+          value={value ?? ""}
+          onChange={(e) => onChange(e.target.value)}
+        >
+          {children}
+        </select>
       ),
-    }
-  ),
-}));
+      {
+        Option: ({ value, children }: any) => (
+          <option value={value}>{children}</option>
+        ),
+      }
+    ),
+  };
+});
 
 vi.mock("@/components/networking", () => ({
   getCallbacksCall: vi.fn(),