refactor(db): 修复异步连接池无界增长，并完成 SQLAlchemy 2.0 迁移与分层归位 (#6320)

app/main.py

@@ -57,7 +57,7 @@ elif SystemUtils.is_frozen():
 
 from app.factory import app
 from app.runtime.config import global_vars, settings
-from app.db.init import init_db, update_db
+from app.startup.database_initializer import init_db, update_db
 
 # 设置进程名
 setproctitle.setproctitle(settings.PROJECT_NAME)
@@ -73,7 +73,7 @@ class MoviePilotServer(uvicorn.Server):
 
 # uvicorn服务
 Server = MoviePilotServer(Config(app, host=settings.HOST, port=settings.PORT,
-                                 reload=settings.DEV, workers=multiprocessing.cpu_count() * 2 + 1,
+                                 reload=settings.DEV, workers=settings.API_WORKERS,
                                  timeout_graceful_shutdown=60))