Updated providers with riverpod

[davidetarsi]

This pull request refactors the project to replace static classes with Riverpod providers to improve state management and code maintainability.

Changes made:

• Integrated the riverpod library to manage application state using providers.
• Refactored widgets to consume state through Riverpod’s ConsumerWidget and ref.watch() where necessary.
• Improved dependency injection and modularity across the codebase.
• Used the built-in code generator to create Riverpod's providers

Benefits:

• Enhanced code scalability and flexibility.
• Improved testing capabilities by decoupling business logic from static dependencies.
• Adherence to Flutter development best practices with modern state management.

Notes for reviewers:

Please check for any overlooked state-sharing dependencies or potential performance bottlenecks after this refactor.