Tracks time when other user logged in on macOS

I got my gf a new M1 Macbook Air recently and set up a user account to try out a few AW things. But today when I used the computer for the second time, AW had logged me as active for several hours a day, time when my gf was presumably using the computer.

No window title was leaked tough (thankfully), it just thought I was staring at the ActivityWatch dashboard for hours each day... (easy to clean the data, at least).

So this is another issue where ActivityWatch is not ready for multi-user systems (see also #75).