Implemented E2E test for full container lifecycle in tests/test_e2e_lifecycle.py **Test Coverage:** 1. test_full_lifecycle - Complete flow: create -> wait for ready -> exec command -> get connect info -> stop -> delete 2. test_lifecycle_with_restart - Create -> stop -> start -> verify running -> delete 3. test_exec_multiple_commands - Create container and execute multiple commands (hostname, os-release, file write/read) 4. test_connect_info_desktop_container - Verify desktop containers include both SSH and VNC connection info **Key Features:** - Uses @requires_incus marker to skip on systems without Incus - Uses @pytest.mark.slow marker for long-running tests - Includes wait_for_job_completion() helper for polling async job completion - Proper cleanup with finally blocks to prevent orphaned containers - Dedicated fixtures (e2e_client, e2e_auth_headers) for E2E tests with longer timeouts **Verification:** - All 182 existing tests pass - 4 new E2E tests collected successfully - Tests correctly skip when Incus is unavailable To run E2E tests on a system with Incus: pytest tests/test_e2e_lifecycle.py -v