fix: batch ha metadata and improve mobile dashboard

tests/ha/test_ha_client.py

@@ -108,6 +108,27 @@ def test_list_entity_metadata_calls_template_api() -> None:
     }
 
 
+def test_list_entity_metadata_batches_template_calls() -> None:
+    responses = []
+    for index in range(3):
+        response = _response()
+        response.text = (
+            f'[{{"entity_id":"sensor.test_{index}",'
+            f'"area_name":"Area {index}","device_name":"Device {index}"}}]'
+        )
+        responses.append(response)
+    client = HaClient(HaClientSettings(url="http://ha.local", token="test-token"))
+    client._session.post = Mock(side_effect=responses)  # type: ignore[method-assign]
+
+    entity_ids = [f"sensor.test_{index}" for index in range(401)]
+    metadata = client.list_entity_metadata(entity_ids)
+
+    assert client._session.post.call_count == 3
+    assert metadata["sensor.test_0"]["area_name"] == "Area 0"
+    assert metadata["sensor.test_1"]["device_name"] == "Device 1"
+    assert metadata["sensor.test_2"]["device_name"] == "Device 2"
+
+
 def test_get_logbook_filters_entity_and_period() -> None:
     response = _response(payload=[{"entity_id": "light.office"}])
     client = _client_with_response(response)