Display screen to gather user information

After a user registers, they will be asked to log in to the app. We need to provide a check in the login screen to check if the user that is logging in is a first-time user or an existing user.

If she/he is a first-time user, redirect the user to the InfoScreen which can be found in the `screens` folder. Gather information about the user and add it to Firebase Realtime Database.

For checking the type of user, you can use Firebase Realtime DB. Check if an entry for the UID of the user is there in the DB or not. If its not there, then this user is a first-time user.

Start by reading the login screen and the InfoScreen in the screens folder, then inspect how Firebase Realtime Database stores entries by user UID. Implement the first-time-user check after login, collect the requested information in InfoScreen, and store it in Firebase. Done means new users are redirected and saved, while existing users are not.

Written by the indexing model from the issue text.