Mark Duotecno entities unavailable when tcp goes down

[Cereal2nd]

Proposed change

When the tcp connection to the duotecno smartbox goes down, mark all entities as unavailble.

This depends on #114320
Can we also add this to 2024.4.0? This will greatly improve the usability of duotecno.

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[davet2001]

Looks good to me!
Thanks @Cereal2nd 👍

[rytilahti]

Now this does update the state only when the entity is created, which is probably what's wanted here?

[Cereal2nd]

i was just testing this, and no the state can be updated during the runtime, and it seems that this is not happening, so i think we still need the property

[rytilahti]

Yes, either a property or setting it inside the update callback. I think both are fine, setting the variable directly saves a bit code and is generally preferred, but the original way you had is also fine. Your call!

[Cereal2nd]

I just reverted my fix

[rytilahti]

LGTM, thanks @Cereal2nd! 👍