feat: implement dynamic decky mutation and fix dot-separated INI sections

tests/test_fleet_api.py

@@ -1,8 +1,7 @@
-import os
 import json
 import pytest
 from fastapi.testclient import TestClient
-from decnet.web.api import app, repo
+from decnet.web.api import app
 import decnet.config
 from pathlib import Path