Refactor Bluetooth ViewModel and HomeScreen logic

[Basler182]

Problem

The BluetoothViewModel currently handles a lot more than it should and is tightly coupled with the Home Screen logic.

Solution

• Create a new component named MessageHandler and extract the message logic currently residing in BluetoothViewModel into this component.
• Inject the MessageHandler into MainActivityViewModel and invoke a new action that will internally call the handler.
• Rename BluetoothViewModel to HomeScreenViewModel to better reflect its purpose.
• Extract Bluetooth-related logic into its own service to promote separation of concerns and improve maintainability.

Additional context

This refactor will simplify the ViewModel, improve the separation of concerns, and make the application easier to test and extend in the future.

Code of Conduct

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