feat: add creative welcome and external works square links

tests/unit/community.test.tsx

@@ -0,0 +1,33 @@
+import { cleanup, fireEvent, render, screen, waitFor } from '@testing-library/react';
+import { afterEach, beforeEach, expect, it, vi } from 'vitest';
+import { invokeIpc } from '@/lib/api-client';
+import { COMMUNITY_URL } from '@/lib/community';
+import { CommunityLink } from '@/components/community/CommunityLink';
+import { CommunityInvitation } from '@/components/community/CommunityInvitation';
+
+vi.mock('@/lib/api-client', () => ({ invokeIpc: vi.fn() }));
+beforeEach(() => { vi.mocked(invokeIpc).mockReset().mockResolvedValue(undefined); });
+afterEach(cleanup);
+
+it('only opens the public explore URL after a click, without fetching or embedding works', async () => {
+  const fetch = vi.spyOn(globalThis, 'fetch');
+  render(<CommunityInvitation />);
+  expect(invokeIpc).not.toHaveBeenCalled();
+  expect(fetch).not.toHaveBeenCalled();
+  expect(document.querySelector('iframe')).toBeNull();
+  fireEvent.click(screen.getByRole('button', { name: '去作品广场逛逛' }));
+  await waitFor(() => expect(invokeIpc).toHaveBeenCalledExactlyOnceWith('shell:openExternal', COMMUNITY_URL));
+  fetch.mockRestore();
+});
+
+it('provides an accessible collapsed sidebar entry and a retry after opening fails', async () => {
+  vi.mocked(invokeIpc).mockRejectedValueOnce(new Error('unavailable'));
+  render(<CommunityLink variant="sidebar" collapsed />);
+  const button = screen.getByRole('button', { name: '作品广场' });
+  fireEvent.click(button);
+  await screen.findByRole('alert');
+  await waitFor(() => expect(button).toBeEnabled());
+  fireEvent.click(button);
+  await waitFor(() => expect(invokeIpc).toHaveBeenCalledTimes(2));
+  expect(screen.queryByRole('alert')).not.toBeInTheDocument();
+});