v2.3.1: Refactor and enhance file handling and GUI functionality

- Updated `files.py` to improve the `get_new_name` function, ensuring it returns a valid path when the upload frame is not found.
- Deleted the `main.py` file in the `upload/honglitong` directory, removing obsolete code related to product uploads.
- Modified `apis.py` in `upload/qiyuehui` to change the type of `category_list` from a list of strings to a list of dictionaries, enhancing data structure clarity.
- Added a new asynchronous function `check_goods_exists` in `gui.py` to verify if a product already exists before processing, improving data integrity.
- Updated various sections in `DataForm` to utilize the new `check_goods_exists` function, streamlining the product validation process.

These changes collectively improve code maintainability and enhance the user experience in the GUI.