Profile Creation Integration

Changes Made

Summary : adding profile creation on first sign in and implementing it into app flow.

Added a ProfileCreationScreen composable that allows the user to customize profile on first sign in. See file ProfileCreation.kt.
The screen was implemented into the app flow in the MainActivity.kt and in the navigation system.
The SignIn.kt file was changed to integrate navigation to the ProfileCreationScreen if there was no IceBreakrr account for the user.
The Firebase FCM token generation was moved from SignIn.kt to the ProfileCreationScreen for this implementation.

Created a DateUtils file in the utils folder to provide some basic date handling functions.