refactor: track background tasks in application lifecycle and clean up codebase

tests/test_api_surface.py

@@ -76,6 +76,7 @@ class ApiSurfaceTest(unittest.TestCase):
     def test_restart_endpoint_calls_restart_state(self):
         import asyncio
         from unittest.mock import MagicMock
+
         from zyrarbot.ui.api.routers.status_router import restart_bot
 
         mock_request = MagicMock()
@@ -88,6 +89,7 @@ class ApiSurfaceTest(unittest.TestCase):
 
     def test_voice_channels_payload_filters_unconnectable_channels(self):
         from unittest.mock import MagicMock
+
         from zyrarbot.ui.api.status_service import StatusService
 
         mock_guild = MagicMock()