"Failed to arm" info to be used in ESPhome

[josch88]

Add an info/event to alarm_control_panel.alarmo to inform Home Assistent that Alarmo failed to arm similar to the MQTT event "FAILED_TO_ARM"

Checklist

• [ x ] I checked for similar existing requests (both open and closed) before posting.
• [ x ] My request is generic, other users may benefit from it too.

Proposal

Any idea is welcome to achieve that ESPhome is informed that Alarmo was not able to arm

Additional info

I am working on a nice ESPhome based Alarmo panel with RFID reader, audio and optical feedback which is already working very well with Alarmo via the Home Assistent API of ESPhome. The only thing I miss is the information that Alarmo can not be armed for example due to an open sensor. I tried to use the open_sensors attribute as a workaround, but as this attribute will only be set to null again after Alarmo has been able to arm successfully.
BTW, I will publish this project as soon as it is done.