fix api integration quality baseline

app/api/v1/__init__.py

@@ -0,0 +1 @@
+"""Version 1 API package."""

app/api/v1/entities.py

@@ -1,10 +1,12 @@
 from __future__ import annotations
 
-from typing import List, Sequence
+from collections.abc import Sequence
 
-from fastapi import APIRouter
+from fastapi import APIRouter, Depends
 
+from app.dependencies import get_ha_reader
 from app.ha.models import HaEntitySummary
+from app.ha.reader import HaReader
 
 router = APIRouter(prefix="/v1", tags=["entities"])
 
@@ -13,7 +15,7 @@ router = APIRouter(prefix="/v1", tags=["entities"])
     "/entities",
     summary="Home-Assistant-Entities auflisten",
     description="Gibt eine kompakte Zusammenfassung aller erreichbaren HA-Entitäten zurück.",
-    response_model=List[HaEntitySummary],
+    response_model=list[HaEntitySummary],
 )
-def list_entities() -> Sequence[HaEntitySummary]:
-    raise NotImplementedError("Integration mit dem HA-Client folgt in separatem Issue.")
+def list_entities(reader: HaReader = Depends(get_ha_reader)) -> Sequence[HaEntitySummary]:
+    return reader.read_entities()