(Mystnodes - Android) Permanent notification

[Zebra72]

Is your feature request related to a problem?
Not really, just want to suggest an additional functionality. It's for now not easy to see if the node is running fine, we need to find and open the app.

Describe the solution you'd like
On solution can be to add an option allowing to activate a permanent notification reflecting minus the current node status and maybe active sessions count and $MYST winnings.

Additional context
By granting the ability to show this notification we can reduce node runners effort on nodes monitoring and maybe increase easylly uptime.