CloudKey/NVR temperature sensor
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**Is your feature request related to a problem? Please describe:**
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I would like to be able to create HomeKit automations based on my CloudKey's temperature. E.g. turn on a fan when temp > X

**Describe the solution you'd like:**
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The temperature appears to be included in the `/api/ws/system` websocket messages, I would like to have this temperature exposed as a temperature sensor.
It is possible that other Protect NVR models do not report a temperature but I don't have any to test against.

**Describe alternatives you've considered:**
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I've considered making a plugin for this myself but it's probably more efficient to have only one plugin deal with Protect.
I don't know of any alternatives that would allow me to get the temperature as a HomeKit sensor.

**Additional context:**
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I know this may be a bit out of scope, but it is data provided by the device that this plugin is already connecting to.

Thanks!

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