You can also re-enable Windows Photo Viewer, which is still installed in Windows 10 and seems to have almost all your requirements.
You need to manipulate Windows Registry using following:
Windows Registry Editor Version 5.00
You can try the Pictureflect Photo Viewer (https://pictureflect.com/). The Software can be downloaded in the Microsoft Store.
It has a free version and it meets all the given requirements. Moreover it has a modern, Windows 10 styled look. I did not try it but this App should work well with touchscreen devices
To work on a per-page basis, you can use GIMP 2.10 > "Import as layers". Then you can rearrange or delete layers and finally export every layer as a page in a PDF. As a caveat, this process makes every page the canvas size.
Can I suggest that it would be a very good idea to change the way that you are working to use a decent distributed Version Control Software such as git, mercurial or such.
Rather than having automatic incremental backup every 60 seconds or so commit to your local checkout every time that you have a significant set of changes, i.e. it is something that you ...
If you are already working with code then I recommend Visual Studio Code since it has an excellent built-in diff tool. Visual Studio Code is a pretty good code editor in its own right so I think it's a good app to have installed along with your other development tools. I use it to work on miscellaneous projects outside of my main IDE.
To use its compare ...
Here https://github.com/vasyaod/parental-control a simple daemon for Linux is provided with following features:
flexible week schedule
convenient yaml config
supporting multiple users
simple web UI (installation of UI is not obligatory) which allows to see
state of consumed time for current date
statistics of consumed time