fix(pi): keep active runs alive during background sleep

tests/unit/auth-routes.test.ts

@@ -901,6 +901,7 @@ describe('auth host api routes', () => {
     expect(response.statusCode).toBe(200);
     expect(response.json()).toEqual({ success: true });
     expect(stop).toHaveBeenCalledOnce();
+    expect(stop).toHaveBeenCalledWith('auth_cleanup');
     expect(closeEventSessions).toHaveBeenCalledOnce();
     expect(providerServiceMock.deleteAccountApiKey).toHaveBeenCalledWith('niancode-user-models');
   });
@@ -927,6 +928,7 @@ describe('auth host api routes', () => {
       success: false,
       error: 'Failed to clear local AI runtime state',
     });
+    expect(stop).toHaveBeenCalledWith('auth_cleanup');
     expect(providerServiceMock.deleteAccountApiKey).toHaveBeenCalledWith('niancode-user-models');
   });