Recommendation is to avoid using the year nomenclature as this
information is already encoded in the git repo. Avoids needing to
repeatly update.
Also updates AUTHORS.txt from current repo with contributor names
Also adds a cancel confirmation dialog.
Also fixes an issue where a thread termination error message is shown
when calling Delete(), because the thread has already exited after
Wait().
Fixes https://gitlab.com/kicad/code/kicad/-/issues/19279
