feat(protocol): add cancellable session interruption

tests/test_public_api_contract.py

@@ -11,7 +11,10 @@ from smartthings_local.protocol.auth import (
     CertificateAuth,
     PskAuth,
 )
-from smartthings_local.protocol.dtls_session import DtlsCoapSession
+from smartthings_local.protocol.dtls_session import (
+    ConnectCancellation,
+    DtlsCoapSession,
+)
 
 
 def _assert_compatible_signature(callable_object, expected: list[str]) -> None:
@@ -81,12 +84,20 @@ def test_dtls_session_keeps_current_consumer_methods():
         "subscribe",
     }
     assert expected <= set(dir(DtlsCoapSession))
+    assert "abort" not in DtlsCoapSession.__dict__
+    assert "quiesce_for_close" not in DtlsCoapSession.__dict__
     _assert_compatible_signature(DtlsCoapSession.connect, ["self"])
     connect_timeout = inspect.signature(DtlsCoapSession.connect).parameters[
         "timeout"
     ]
     assert connect_timeout.kind is inspect.Parameter.KEYWORD_ONLY
     assert connect_timeout.default is None
+    connect_cancel = inspect.signature(DtlsCoapSession.connect).parameters[
+        "cancel"
+    ]
+    assert connect_cancel.kind is inspect.Parameter.KEYWORD_ONLY
+    assert connect_cancel.default is None
+    assert callable(ConnectCancellation().set)
     _assert_compatible_signature(
         DtlsCoapSession.get,
         [