- Fix type annotation errors in transport_registry.py and __init__.py
- Fix line length violations in test files (E501 errors)
- Fix missing return type annotations
- Fix cryptography NameAttribute type errors with type: ignore
- Fix ExceptionGroup import for cross-version compatibility
- Fix test failure in test_wss_listen_without_tls_config by handling ExceptionGroup
- Fix len() calls with None arguments in test_tcp_data_transfer.py
- Fix missing attribute access errors on interface types
- Fix boolean type expectation errors in test_js_ws_ping.py
- Fix nursery context manager type errors
All tests now pass and linting is clean.
