Better switch status indicators

[iljarotar]

Description

Currently, there is a color-encoded status indicator for the switches that shows green, yellow or red depending on

• how long ago the last sync was
• if the last sync returned an error
• if all ports are up

Showing the status in this way is problematic for several reasons:

• color-encoded indicators without a supportive non-color-encoded element can't be interpreted by people with color vision deficiency or if someone uses a color different than white or black for their terminal font
• the colors can mean too many different things, e.g. a switch is shown yellow if the last sync is too long ago or if some ports are down

Ideally, the switch list should provide all information at once.

• was the last sync within a time range considered good, okay or bad?
• did the last sync return an error?
• do some of the ports have a status different from their desired status?

We should introduce multiple emojis for the different kinds of status information like we have for the machines.

[Gerrit91]

Good issue. Some suggestions for emojis:

• Not syncing in time: ⏱️
• Sync error: ⚡
• Unexpected port state: 🔌 or ⬇️