Unfortunately, TonCut does not have such a feature, although this does not mean it's impossible.

To use TonCut as a warehouse, after the optimization process has finished, press Save button (it is located on the left bottom corner of the screen) and select Pieces and sheets leftovers option and Save waste as sheets. Now press Save and select/type name for the warehouse file. It is best to save it in subsequent files, for instance: warehouse001, warehouse002, etc. This way you can always return to the previous version.

Now you have all the remaining sheets and pieces in the file. Additionally, reusable waste is also stored as sheets.

Now you can load the file (for instance: warehouse001, warehouse002, etc.) and enter new orders (pieces) and/or refill the stock.

After the next optimization, save again pieces and sheets leftovers to the file, for instance: warehouse001, warehouse002, etc.