Improve Plant Monitor integration handling of unavailability

[rusthedj]

Integration name

Plant Monitor

Link to integration documentation on our website

https://www.home-assistant.io/integrations/plant/

Describe the enhancement

I use HHCC plant sensors over BLE to monitor plants. These often become temporarily unavailable (especially but not exclusively where they are at the limits of my Bluetooth reception), resulting in the Plant Monitor entity showing status "Problem" in red wherever its status is displayed, which makes it hard to tell whether any plants really need attention or are just unavailable at the time.

The key attribute for me is moisture, so I've created template sensors which show the previous moisture value while the HHCC sensor is unavailable, but it seems that if any attribute of a plant entity is unavailable, the state of the entity still becomes "problem" even if some are still available.

Two requests:

1. The plant entity state should be "unavailable" or "unknown" with state color gray instead of "problem" in red if all attributes are unavailable or unknown.
2. If only some attributes are not available, these could be ignored so that only the available attributes are used to determining whether the state should be "problem" or "ok". This behaviour may not suit everyone, so as an alternative the state could also be "unavailable" or "unknown" if any attribute is unavailable or unknown.

Thanks, Rory

Use cases

This would solve the problem of unavailable plant sensors causing an unhelpful Plant Monitor state.

Anything else?

No response

[github-actions[bot]]

🏷️ I've automatically added the integration: plant label to help categorize this feature request.