fix api integration quality baseline

app/ha/client.py

@@ -2,6 +2,7 @@ from __future__ import annotations
 
 import logging
 from dataclasses import dataclass
+from typing import Any
 
 import requests
 
@@ -24,10 +25,14 @@ class HaClient:
             "Content-Type": "application/json",
         })
 
-    def list_entities(self) -> list[dict[str, object]]:
+    def list_entities(self) -> list[dict[str, Any]]:
         response = self._session.get(
             f"{self._settings.url}/api/states",
             timeout=self._settings.timeout_seconds,
         )
         response.raise_for_status()
-        return response.json()
+        payload = response.json()
+        if not isinstance(payload, list):
+            msg = "Home Assistant states response must be a list."
+            raise TypeError(msg)
+        return payload

app/ha/reader.py

@@ -1,9 +1,10 @@
 from __future__ import annotations
 
 from collections.abc import Sequence
+from typing import Any
 
 from app.ha.client import HaClient
-from app.ha.models import HaEntitySummary, HaState
+from app.ha.models import HaEntitySummary
 
 
 class HaReader:
@@ -18,14 +19,21 @@ class HaReader:
             if "." not in entity_id:
                 continue
             domain = entity_id.split(".", 1)[0]
-            attributes = item.get("attributes") or {}
+            raw_attributes = item.get("attributes") or {}
+            attributes: dict[str, Any] = raw_attributes if isinstance(raw_attributes, dict) else {}
             summaries.append(
                 HaEntitySummary(
                     entity_id=entity_id,
                     domain=domain,
-                    state_class=str(attributes.get("state_class") or ""),
-                    device_class=str(attributes.get("device_class") or ""),
-                    unit_of_measurement=str(attributes.get("unit_of_measurement") or ""),
+                    state_class=_optional_str(attributes.get("state_class")),
+                    device_class=_optional_str(attributes.get("device_class")),
+                    unit_of_measurement=_optional_str(attributes.get("unit_of_measurement")),
                 )
             )
         return summaries
+
+
+def _optional_str(value: object) -> str | None:
+    if value is None or value == "":
+        return None
+    return str(value)