M8-T17: add Home Assistant thermal entities

tests/test_ha_discovery.py

@@ -15,7 +15,7 @@ Coverage:
 
 from __future__ import annotations
 
-from datetime import datetime, timezone
+from datetime import datetime, timedelta, timezone
 from pathlib import Path
 from typing import Any
 from unittest.mock import MagicMock, patch
@@ -1361,3 +1361,20 @@ def test_settings_payload_includes_ha_state_topic_prefix() -> None:
     assert payload["ha_state_topic_prefix"] == "my_prefix", (
         f"Expected 'my_prefix', got {payload['ha_state_topic_prefix']!r}"
     )
+
+
+def test_stale_m8_entities_includes_ended_electricity_meter(disco_db) -> None:
+    """An electricity swap clears exactly the old Meter's two discovery configs."""
+    from app.models.energy import Meter
+    from app.services.ha_discovery import _stale_m8_entities
+
+    now = datetime.now(timezone.utc)
+    with Session(disco_db) as session:
+        old = Meter(label="old", commodity="electricity", started_at=now - timedelta(days=1),
+                    ended_at=now, reason="meter_swap", note=None, created_at=now)
+        current = Meter(label="current", commodity="electricity", started_at=now,
+                        ended_at=None, reason="meter_swap", note=None, created_at=now)
+        session.add_all((old, current))
+        session.commit()
+        keys = {entity.key for entity in _stale_m8_entities(session)}
+        assert keys == {f"meter.{old.uuid}.total", f"meter.{old.uuid}.today"}