The translations are not stored in a synthetic package anymore, but the
files are just copied to a specific folder so it can be more easily imported
Also, flutter_barcode_scanner was replaced by simple_barcode_scanner since
the first hasn't been updated in 3 years and was already causing problems
for some time
This allows the user to use the system settings as well, and not always force
light or dark mode in the app. Also move the logic to the UserProvider and
do some light refactoring.
