refactor: clean up imports and improve code formatting in various modules

src/arbitrade/api/routes.py

@@ -1479,7 +1479,6 @@ async def dashboard_api_pairings_toggle(request: Request) -> HTMLResponse:
 @router.post("/dashboard/api/pairings/sync", response_class=HTMLResponse)
 async def dashboard_api_pairings_sync(request: Request) -> HTMLResponse:
     """Sync pairings from Kraken and return refreshed table."""
-    from arbitrade.config.pairing_sync import sync_pairings_from_kraken
 
     store = request.app.state.store
     kraken = getattr(request.app.state, "kraken_client", None)

src/arbitrade/logging/db_sink.py

@@ -22,7 +22,8 @@ class DbSinkProcessor:
     """
 
     def __init__(self) -> None:
-        self._queue: asyncio.Queue[dict[str, Any]] = asyncio.Queue(maxsize=2000)
+        self._queue: asyncio.Queue[dict[str, Any]
+                                   ] = asyncio.Queue(maxsize=2000)
         self._consumer_task: asyncio.Task[None] | None = None
 
     def __call__(self, logger: Any, method_name: str, event_dict: dict[str, Any]) -> dict[str, Any]:
@@ -52,7 +53,7 @@ class DbSinkProcessor:
             pass
         self._consumer_task = None
         # Flush remaining
-        await self._flush(store=None)
+        await self._flush(store=None)  # type: ignore[call-arg]
 
     async def _consume(self, store: PgStore) -> None:
         repo = LogRepository(store)
@@ -80,7 +81,8 @@ class DbSinkProcessor:
         level = str(event.pop("level", "info")).upper()
         logger = str(event.pop("logger", "root"))
         message = str(event.pop("event", event.pop("message", "")))
-        context = {k: v for k, v in event.items() if not k.startswith("_")} if event else None
+        context = {k: v for k, v in event.items(
+        ) if not k.startswith("_")} if event else None
 
         record = LogRecord(
             recorded_at=recorded_at,
@@ -120,4 +122,4 @@ def db_sink_processor(
     logger: Any, method_name: str, event_dict: dict[str, Any]
 ) -> dict[str, Any]:
     """Standalone processor function wrapping the singleton."""
-    return _db_sink(logger, method_name, event_dict)
+    return _db_sink(logger, method_name, event_dict)

src/arbitrade/storage/repositories.py

@@ -1,7 +1,7 @@
 from __future__ import annotations
 
 from dataclasses import dataclass
-from datetime import UTC, datetime, timedelta
+from datetime import datetime
 from typing import Any
 
 import orjson