Generate only one *.strings file

[borut-t]

Is your feature request related to a problem? Please describe.
Currently, Lingua generate one strings file per section.

Describe the solution you'd like
We should have a toggle in the Lingua app to allow generating only one (aggregated) strings file.

[borut-t]

Let's not do this ticket. Xcode 16 brought us Folders, therefore files are added automatically.
I would just update the instructions in readme file to optionally add files manually if folders are not there.