Fix SMART temperature always reporting null.

Real drives report attribute 194 raw values like "52 (Min/Max 16/57)"
which int() cannot parse, so every drive's temperature was null.
Prefer pySMART's `temperature` property, which parses these formats
and also works for NVMe devices that have no ATA attribute table.

Verified on real hardware (WD100EMAZ over USB-SAT): 51-53C now
reported where null was returned before.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

controller/lib/smart.py

@@ -62,7 +62,16 @@ def _get_device_smart(device) -> dict:
 
 
 def _get_temperature(device) -> Optional[int]:
-    """Get drive temperature from SMART attributes."""
+    """Get drive temperature.
+
+    Prefer pySMART's `temperature` property: it parses real-world raw
+    values like "52 (Min/Max 16/57)" that int() cannot, and works for
+    NVMe devices which have no ATA attribute table.  Fall back to the
+    plain attributes for devices where the property is unavailable.
+    """
+    temp = getattr(device, "temperature", None)
+    if isinstance(temp, int):
+        return temp
     temp = _get_attribute(device, "Temperature_Celsius")
     if temp is None:
         temp = _get_attribute(device, "Airflow_Temperature_Cel")

controller/test/test_smart.py

@@ -119,11 +119,47 @@ class TestGetTemperature:
     def test_returns_none_if_not_found(self):
         """Should return None if no temperature attribute."""
         mock_device = mock.Mock()
+        mock_device.temperature = None
         mock_device.attributes = []
 
         result = _get_temperature(mock_device)
         assert result is None
 
+    def test_prefers_pysmart_temperature_property(self):
+        """Real drives report raw values like '52 (Min/Max 16/57)' which
+        int() cannot parse; pySMART's temperature property handles them."""
+        mock_attr = mock.Mock()
+        mock_attr.name = "Temperature_Celsius"
+        mock_attr.raw = "52 (Min/Max 16/57)"
+
+        mock_device = mock.Mock()
+        mock_device.temperature = 52
+        mock_device.attributes = [mock_attr]
+
+        result = _get_temperature(mock_device)
+        assert result == 52
+
+    def test_pysmart_temperature_property_for_nvme(self):
+        """NVMe devices have no ATA attribute table, only the property."""
+        mock_device = mock.Mock()
+        mock_device.temperature = 38
+        mock_device.attributes = None
+
+        result = _get_temperature(mock_device)
+        assert result == 38
+
+    def test_ignores_non_int_temperature_property(self):
+        """A missing/bogus temperature property falls back to attributes."""
+        mock_attr = mock.Mock()
+        mock_attr.name = "Temperature_Celsius"
+        mock_attr.raw = "35"
+
+        mock_device = mock.Mock()  # .temperature is a Mock, not an int
+        mock_device.attributes = [mock_attr]
+
+        result = _get_temperature(mock_device)
+        assert result == 35
+
 
 class TestGetAttribute:
     """Tests for _get_attribute function."""