phase 15: fix ruff lint errors across services

services/api/app.py

@@ -20,15 +20,15 @@ from typing import Any, Optional
 
 import asyncpg
 from fastapi import FastAPI, HTTPException, Query, Request
+from prometheus_client import CONTENT_TYPE_LATEST, generate_latest
 from starlette.middleware.base import BaseHTTPMiddleware
+from starlette.responses import Response
 
+from services.extractor.metrics import get_model_performance_summary
 from services.shared.audit import get_entity_audit_trail, get_order_audit_trail
 from services.shared.config import load_config
 from services.shared.db import get_pg_pool
 from services.shared.logging import new_trace_id, set_trace_context, setup_logging
-from services.extractor.metrics import get_model_performance_summary
-from prometheus_client import generate_latest, CONTENT_TYPE_LATEST
-from starlette.responses import Response
 
 logger = logging.getLogger("query_api")
 
@@ -339,7 +339,7 @@ async def list_trends(
     offset: int = 0,
 ):
     """List trend summaries with optional filters."""
-    conditions = [f"entity_type = $1"]
+    conditions = ["entity_type = $1"]
     params: list[Any] = [entity_type]
     idx = 2