rework-onboarding (#7)

Onboarding completato, ora super rapido e top

Reviewed-on: http://catelliub.zapto.org:3000/brontomark/flux/pulls/7
Co-authored-by: Mark M2 Macbook <marco@catelli.it>
Co-committed-by: Mark M2 Macbook <marco@catelli.it>

GEMINI.md

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+## General Instructions
+
+- Prefer the Flutter clean architecture
+- Prefer Cubit over Bloc and Stateful where is good practice
+- Data Models must always extend Equatable, have copyWith, empty and fromMap, toMap when they'll be saved in db
+- Use GoRouter
+- Use Enums when possible instead of hardcoded Strings or Numbers for better readability and less error prone