[Feature request]: Please display "last seen" for offline sensors

[AndKe]

Is your feature request related to a problem? Please describe

Sometimes one see an sensor offline, some sensors have very long time between reporting, and will time out.
Please display "last seen" time or time since last seen. This would maek it easy to see at a glance if there is an actual issue with the sensor, or if it simply timed out.

Describe the solution you'd like

Please display "last seen" time or time since last seen. near the red "Offline" in the Availability column.

Describe alternatives you've considered

Additional context

[github-actions]

This issue is stale because it has been open 60 days with no activity. Remove stale label or comment or this will be closed in 7 days

[AndKe]

bump

[github-actions]

This issue is stale because it has been open 60 days with no activity. Remove stale label or comment or this will be closed in 7 days

[AndKe]

bump