More granularity & learning from competition

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I came here after getting frustrated with the quite old Workrave and trying Stretchly, which is unfortunately written with Electron and barely configurable - however, it has some sane defaults I would like to see as options here as well:

• the ability to disable postponement and skipping for each break type - there should be nothing urgent enough to postpone a short break, however I might want to postpone a long break for a bit to finish something
• amount of postponements is limited - dunno how SafeEyes handles that, as #326 is apparently still not published
• ability to continue typing into the break - sometimes only a few words are missing, and I like the ability to have a slight grace period to finish something if you need to but don't want to postpone the break

What I have been missing in all of these tools is the flexibility to add and remove types of breaks - why does it have to be a single type of short and a single type of long break? Maybe I additionally want to enforce a break of at least 15 minutes every 2 hours, with its own prompts. These could then even be refined by having different modes (e.g. writing, working, gaming) where different types of breaks are enabled. Currently, I usually have to disable my break timer tool when gaming, but that's not really what I want in the long term.

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Also: https://github.com/slgobinath/SafeEyes/pull/358#issuecomment-747983890