intro screen for choosing language.

When the user first opens the app, he should see the list of available languages and choose one to learn.
It should be intro screen with several stages.
The first is the title of the app and the logo (currently exists)
The second is an introduction to the app and the method in several sentences.
The third is choosing a language to learn or skip.
For this intro screen I recommend using the package [introduction_screen](https://pub.dev/packages/introduction_screen) , example of usage in our architecture can be found here https://github.com/guyluz11/infinite_horizons/blob/main/lib/presentation/pages/intro_page.dart