style: auto-format with black + isort

apps/api/app/api/routes/edit_plans.py

@@ -605,9 +605,9 @@ def save_plan_as_template(
 from .edit_plans_ai import router as ai_router
 from .edit_plans_clips import router as clips_router
 from .edit_plans_clips_batch import router as clips_batch_router
+from .edit_plans_cover import router as cover_router
 from .edit_plans_generation import router as generation_router
 from .edit_plans_timeline import router as timeline_router
-from .edit_plans_cover import router as cover_router
 
 router.include_router(generation_router)
 router.include_router(ai_router)

apps/api/app/services/cover_service.py

@@ -271,6 +271,6 @@ class CoverService:
                 if result2.returncode != 0:
                     raise RuntimeError(f"FFmpeg 抽帧失败: {result2.stderr[-300:]}")
         except subprocess.TimeoutExpired as e:
-            raise RuntimeError(f"FFmpeg 抽帧超时") from e
+            raise RuntimeError("FFmpeg 抽帧超时") from e
         except FileNotFoundError as e:
             raise RuntimeError("FFmpeg 不可用") from e