delivery(ahmed-sami): deliver the requested task

[asamiz]

What

• I added the onboarding flow using react-native-onboarding-swiper contains:
  -> First screen with QLASH logo and a simple welcome message.
  -> The second screen with the title and subtitle shows one of the app features.
  -> The third screen contains a title and a subtitle showing one of the app features.
• The user can swipe between all the screens until the last screen that contains a done button when the user clicks it the app navigates to the home screen
• I added another flow when the user clicks on the done button, the app never shows the onboarding screens again until he/she removes the app or clears the memory I used @react-native-async-storage/async-storage to save a flag inside the app memory to achieve this flow.

Why

It is a part of the recruitment process of the QLASH team.