fix(fridge): stop switch turn-off silently sending 'On'

Six fridge SwitchDesc write_fns built their payload with
`'On' if p else 'Off'`. The switch platform passes the literal
string 'Off' on turn-off, which is truthy, so the guard always
produced 'On' -- turning these switches off silently re-sent On
and they could never be turned off:

  - ICEMAKER_NIGHTTIME (ice.night.status)
  - STATUS_LOCK helper (devicecontrol + device.sound)
  - DEFROST_DELAY (delayDefrost)
  - WELCOME_LIGHTING (status)
  - CABINET_LIGHT dim (light.dimming.status)
  - ICEMAKER_STATUS_FALLBACK (iceMaker)

Compare `p == 'On'` instead, matching the pattern the other
capability files already use. Adds a regression test asserting
every affected write_fn sends 'Off' on 'Off' and 'On' on 'On'.

custom_components/localthings/registry/capabilities/fridge.py

@@ -92,7 +92,7 @@ ICEMAKER_NIGHTTIME = Capability(
                    value_fn=lambda v: v == 'On',
                    write_fn=lambda p, rep, href=None: (
                        ['icemaker', 'nighttime', 'vs', '0'],
-                       {'ice.night.status': 'On' if p else 'Off'})),
+                       {'ice.night.status': 'On' if p == 'On' else 'Off'})),
     ),
 )
 
@@ -168,7 +168,7 @@ DOOR_ALERT = Capability(
 def _status_lock_write(field):
     return lambda p, rep, href=None: (
         ['status', 'lock', 'vs', '0'],
-        {field: 'On' if p else 'Off'}
+        {field: 'On' if p == 'On' else 'Off'}
     )
 
 
@@ -212,7 +212,7 @@ DEFROST_DELAY = Capability(
                    value_fn=lambda v: v == 'On',
                    write_fn=lambda p, rep, href=None: (
                        ['defrost', 'delay', 'vs', '0'],
-                       {'x.com.samsung.da.delayDefrost': 'On' if p else 'Off'})),
+                       {'x.com.samsung.da.delayDefrost': 'On' if p == 'On' else 'Off'})),
     ),
 )
 
@@ -300,7 +300,7 @@ WELCOME_LIGHTING = Capability(
                    value_fn=lambda v: v == 'On',
                    write_fn=lambda p, rep, href=None: (
                        ['proximity', 'vs', '0'],
-                       {'status': 'On' if p else 'Off'})),
+                       {'status': 'On' if p == 'On' else 'Off'})),
     ),
 )
 
@@ -440,7 +440,7 @@ CABINET_LIGHT = Capability(
                    value_fn=lambda v: v == 'On',
                    write_fn=lambda p, rep, href=None: (
                        ['cabinet', 'light', 'total', 'vs', '0'],
-                       {'light.dimming.status': 'On' if p else 'Off'})),
+                       {'light.dimming.status': 'On' if p == 'On' else 'Off'})),
     ),
 )
 
@@ -669,7 +669,7 @@ ICEMAKER_STATUS_FALLBACK = Capability(
                    value_fn=lambda v: v == 'On',
                    write_fn=lambda p, rep, href=None: (
                        ['icemaker', 'status', 'vs', '0'],
-                       {'x.com.samsung.da.iceMaker': 'On' if p else 'Off'})),
+                       {'x.com.samsung.da.iceMaker': 'On' if p == 'On' else 'Off'})),
     ),
 )
 

tests/test_fridge_capabilities.py

@@ -258,3 +258,39 @@ class TestRefrigeratorAiEnergyLevelFixtureCoverage:
         assert unbound == []
         state = flatten(bound, resources)
         assert state['ai_energy_level'] == '1'
+
+
+class TestSwitchOffIsNotInverted:
+    """Regression: several fridge SwitchDesc write_fns used ``'On' if p else 'Off'``.
+
+    The switch platform passes the literal string ``'Off'`` on turn-off (and
+    ``'On'`` on turn-on). ``'Off'`` is a non-empty, truthy string, so
+    ``'On' if p else 'Off'`` always evaluated to ``'On'`` — turning the switch
+    OFF silently re-sent ``On`` and the switch could never be turned off. The
+    guard must compare ``p == 'On'`` (as the other capability files already do).
+    """
+
+    # (switch descriptor, payload key it writes)
+    CASES = [
+        (fridge.ICEMAKER_NIGHTTIME.entities[0], 'ice.night.status'),
+        (fridge.STATUS_LOCK.entities[0], 'x.com.samsung.da.ado.devicecontrol'),
+        (fridge.STATUS_LOCK.entities[1], 'x.com.samsung.da.device.sound'),
+        (fridge.DEFROST_DELAY.entities[0], 'x.com.samsung.da.delayDefrost'),
+        (fridge.WELCOME_LIGHTING.entities[0], 'status'),
+        (fridge.CABINET_LIGHT.entities[1], 'light.dimming.status'),
+        (fridge.ICEMAKER_STATUS_FALLBACK.entities[0], 'x.com.samsung.da.iceMaker'),
+    ]
+
+    def test_turning_off_sends_off(self):
+        for desc, key in self.CASES:
+            _segs, payload = desc.write_fn('Off', {})
+            assert payload[key] == 'Off', (
+                f"{desc.key}: OFF must send 'Off', got {payload[key]!r} (inverted)"
+            )
+
+    def test_turning_on_sends_on(self):
+        for desc, key in self.CASES:
+            _segs, payload = desc.write_fn('On', {})
+            assert payload[key] == 'On', (
+                f"{desc.key}: ON must send 'On', got {payload[key]!r}"
+            )