Swap between UnifiedPush and Websocket when server is down/up

[schklom]

Guidelines

• Yes, I have searched the existing requests

Feature Description

Follow-up for mollyim#11

Feature description

The idea originated in the Matrix chat, thanks to S1m (I assume is @p1gp1g) :)

Problem

If the mollysocket server goes down, Molly simply stops receiving notifications until the server owner notices by themselves and starts it back up.

Solution

Every X time (e.g. every hour), the mollysocket server can ping Molly-UP.
As S1m puts it in the chat

every hour mollysocket sends a ping, if the phone doesn't get a ping for more than one hour, it can assume mollysocket is down

then switch back to UP if it receives a ping

I would also love to get a Molly-UP (low-priority maybe?) notification when the server is considered down so I know that I (or a friend) need to restart it.