Add Drum Clean+ sensors for dishwasher

The dishwasher's /course/vs/0 options[] array carries the same
WashingTimes_/DrumCleanProposal_/DrumCleanLog_ trio already read by
washer.py (issue #9) and dryer.py (issue #258), confirmed against a
live dump, but dishwasher.py never wired the shared
laundry.drum_clean_cycles_remaining/drum_clean_last_cleaned readers
in. Add the two sensors to CYCLE_OPTIONS the same way, plus tests and
an updated golden fixture.

tests/fixtures/golden/dishwasher.json

@@ -8,6 +8,8 @@
     "cycle_active",
     "delay_start_hours",
     "diagnosis_status",
+    "drum_clean_cycles_remaining",
+    "drum_clean_last_cleaned",
     "energy_kwh",
     "energy_saved_kwh",
     "finish_time",
@@ -40,6 +42,8 @@
     "samsung_dishwasher_delay_start_hours",
     "samsung_dishwasher_diagnosis_start",
     "samsung_dishwasher_diagnosis_status",
+    "samsung_dishwasher_drum_clean_cycles_remaining",
+    "samsung_dishwasher_drum_clean_last_cleaned",
     "samsung_dishwasher_energy_kwh",
     "samsung_dishwasher_energy_saved_kwh",
     "samsung_dishwasher_finish_time",