Add source_site_id to ActiveSite model and implement unique constraint. Update serializers and views for site registration and claiming. Enhance tests for site registration and claiming functionality.

components/__tests__/SettingsPage.test.tsx

@@ -156,7 +156,7 @@ describe('SettingsPage city site registry', () => {
     render(<SettingsPage />);
     await screen.findByText('Sukawarna');
 
-    fireEvent.change(screen.getByPlaceholderText('Contoh: Sukawarna'), {
+    fireEvent.change(screen.getByPlaceholderText('sukawarna'), {
       target: { value: 'Cikupa' },
     });
     fireEvent.click(screen.getByRole('button', { name: 'Tambah ke daftar' }));
@@ -164,12 +164,8 @@ describe('SettingsPage city site registry', () => {
     await waitFor(() => expect(createMock).toHaveBeenCalledTimes(1));
     expect(createMock).toHaveBeenCalledWith({
       code: 'cikupa',
-      name: 'Cikupa',
-      is_active: true,
     });
-  });
-
-  it('lets GM request a BUH', async () => {
+  });  it('lets GM request a BUH', async () => {
     requestMock.mockResolvedValue({
       ...authState.user,
       managed_by_pending: 2,