fix: use KLAP v2 transport for IOT devices with login version 2 (#1731)

Some IOT-family devices keep the legacy IOT command set after a firmware
update but upgrade their KLAP authentication to login version 2 (sha256 hashing).

This change selects `KlapTransportV2` for `IOT.KLAP` devices that advertise
`login_version >= 2`, matching the transport already used for `SMART.KLAP`.
Devices with login version 1 (or unset) are unchanged and continue to use the v1 `KlapTransport`.

Co-authored-by: Claude Opus 4.8 <noreply@anthropic.com>

kasa/device_factory.py

@@ -239,4 +239,10 @@ def get_protocol(config: DeviceConfig, *, strict: bool = False) -> BaseProtocol
     if not (prot_tran_cls := supported_device_protocols.get(protocol_transport_key)):
         return None
     protocol_cls, transport_cls = prot_tran_cls
+    if (
+        protocol_transport_key == "IOT.KLAP"
+        and ctype.login_version
+        and ctype.login_version >= 2
+    ):
+        transport_cls = KlapTransportV2
     return protocol_cls(transport=transport_cls(config=config))

tests/test_device_factory.py

@@ -259,6 +259,18 @@ ET = DeviceEncryptionType
             KlapTransport,
             id="iot-klap",
         ),
+        pytest.param(
+            CP(DF.IotSmartPlugSwitch, ET.Klap, login_version=1, https=False),
+            IotProtocol,
+            KlapTransport,
+            id="iot-klap-v1",
+        ),
+        pytest.param(
+            CP(DF.IotSmartPlugSwitch, ET.Klap, login_version=2, https=False),
+            IotProtocol,
+            KlapTransportV2,
+            id="iot-klap-v2",
+        ),
         pytest.param(
             CP(DF.IotSmartPlugSwitch, ET.Xor, https=False),
             IotProtocol,