You can use change tracking to log details about workbook changes every time that you save a workbook. This change history (...includes the name of the person who made each change, when the change was made, and what data was changed) can help you identify any changes that were made to the data in the workbookA side-effect of tracking changes is that the file is shared. Sharing has a number of issues (not least that such files are more prone to corruption) but I'm not sure if that's the case when the file is not being simultaneously opened by more than one user.
Keep in mind that the Target can be multiple cells so when the selection changes so you will need to capture every cell in the selection. Also, the Target to the Change event can be multiple cells for an action like Fill Down.
Here is a proof of concept that ignores the issue of multiple cells being selected or changing.
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