fix issue

app/database.py

@@ -33,6 +33,8 @@ Path(sqlite_path).parent.mkdir(parents=True, exist_ok=True)
 engine = create_async_engine(
     f"sqlite+aiosqlite:///{sqlite_path}",
     echo=False,
+    pool_size=1,
+    max_overflow=0,
 )
 
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