Use version 20 which is the current latest.
Fix bug clang-tidy found if reading the save file fails.
Format code per clang-format-20
I surpressed all new warnings in clang-tidy but we will probably want to
enable and fix some of them.
run-clang-tidy is used instead of calling clang-tidy directly in order
to automatically pull all source files.
* Enables bugprone- checks.
* Enables a couple more modernize checks.
Most of the changes are avoiding implicit narrowing conversions.
There was a bug caught and fixed fixed with the string comparison in iso_fs.
bugprone-suspicious-enum-usage was disabled due to a large number of
false positives with wxWidgets.
