Fix C1 (switch discovery), C2 (power write_fn), I2 (golden oracle)

C1: SwitchDesc MQTT discovery now emits payload_on/off='On'/'Off',
state_on/off='On'/'Off', and a Jinja2 boolean-to-string value_template
so HA can correctly interpret and command switch entities.

C2: POWER write_fn corrected — path is ['power','vs','0'] segment list
(not a single slash-prefixed string), and payload comparison is
p == 'On' (not truthiness) so 'Off' can actually be sent.

I2: Golden regression oracle strengthened to exact equality for both
state_keys and discovery_unique_ids; prior subset-only check allowed
over-production to go undetected. Two golden tests now fail revealing
stale fixtures (dishwasher: +3 keys; refrigerator: +9 keys) — fixtures
intentionally NOT updated, human review required.

tests/test_adapter.py

@@ -10,6 +10,11 @@ def _bound(resources):
     return discover(resources, reg)
 
 
+def _bound_with_power(resources):
+    reg = {c.href: c for c in (common.KIDS_LOCK, common.ENERGY_METER, common.POWER)}
+    return discover(resources, reg)
+
+
 def test_flatten_applies_value_fn(dishwasher_resources):
     rd = build_runtime_descriptor(
         _bound(dishwasher_resources), topic_prefix='t', ha_prefix='homeassistant',
@@ -38,3 +43,17 @@ def test_discovery_payloads_have_unique_ids(dishwasher_resources):
     # payloads are JSON bytes carrying unique_id
     cfg = json.loads(next(p for t, p in rd.discovery_payloads if 'child_lock' in t))
     assert cfg['unique_id'] == 'samsung_dishwasher_child_lock'
+
+
+def test_switch_discovery_config_has_correct_payloads(dishwasher_resources):
+    rd = build_runtime_descriptor(
+        _bound_with_power(dishwasher_resources), topic_prefix='samsung_dishwasher',
+        ha_prefix='homeassistant', device_name='Dishwasher', model='M',
+        name='dishwasher', default_port=49154)
+    cfg = json.loads(next(p for t, p in rd.discovery_payloads if 'power_switch' in t))
+    assert cfg['payload_on'] == 'On'
+    assert cfg['payload_off'] == 'Off'
+    assert cfg['state_on'] == 'On'
+    assert cfg['state_off'] == 'Off'
+    assert 'On' in cfg['value_template']
+    assert 'Off' in cfg['value_template']