Add Pydantic models and FastAPI router structure for agent and backend

backend/app/routers/objects.py

@@ -0,0 +1,19 @@
+from fastapi import APIRouter, HTTPException
+
+from app.schemas import EntityResponse, ListResponse, NetObject
+from app.services.store import OBJECTS
+
+router = APIRouter(prefix='/objects', tags=['objects'])
+
+
+@router.get('', response_model=ListResponse[NetObject])
+def list_objects() -> ListResponse[NetObject]:
+    return ListResponse(count=len(OBJECTS), items=OBJECTS)
+
+
+@router.get('/{object_id}', response_model=EntityResponse[NetObject])
+def get_object(object_id: str) -> EntityResponse[NetObject]:
+    for item in OBJECTS:
+        if item.id == object_id:
+            return EntityResponse(item=item)
+    raise HTTPException(status_code=404, detail='Object not found')