Notification cooldown
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**Is your feature request related to a problem? Please describe:**
I have 9 cameras covering all sides of my house (2 per corner + doorbell). When anyone is outside, particularly when I get a delivery, I get back to back repeated notifications from each camera as the person walks around to the front door and back to the driveway.

**Describe the solution you'd like:**
I would like the option to have a per-camera notification cooldown and/or a global notification cooldown. Bonus points if I can have it be per smart notification type (e.g. person vs car).

**Describe alternatives you've considered:**
I haven't discovered any alternatives. If mowers are outside, I will usually mute notifications for an hour (built-in Apple Home feature).

**Additional context:**
![IMG_3DB979AEC0D0-1](https://user-images.githubusercontent.com/77516/227590864-d4e9192a-ad5a-4d0c-adad-437a1a2cf628.png)
