fix: reset devices list when stopLiveSync method is called

[Fatme]

When stopLiveSync method is called, we want to reset devices list and emit deviceLost event for all connected devices.

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What is the current behavior?

deviceLost event is not emitted when there are connected devices and stopLiveSync method is called

What is the new behavior?

deviceLost event is emitted when there are connected devices and stopLiveSync method is called