Show unconnected but nearby bluetooth devices

**Is your feature request related to a problem? Please describe.**
No, just something that would be nice

**Describe the solution you'd like**
It would be great to see a list of unconnected but nearby bluetooth devices. Is that possible? Right now you can see devices that are listed in "paired devices" even if they are unplugged or far away/unconnectable. The only other attributes show devices you are fully connected to. I want to be able to sense that I am within range of a specific BT device. Kind of the opposite of the beacon functionality. It is not possible to put an internet connected ESP device for room assistant where I'm trying to accomplish this so I need the phone to "know" about the devices it can see. I don't need it to update nearly as frequently as a beacon would either. A "nearby_devices" attribute on the `bluetooth_connection` sensor would be a great feature!

**Describe alternatives you've considered, if any**
I've tried to rig up an alternate solution in Tasker and calling the `[python_script.set_state](https://community.home-assistant.io/t/how-to-manually-set-state-value-of-sensor/43975/2)` service via the HA Tasker plugin, but manually pushing sensor updates causes other issues and I'd prefer if HA handled it with it's state machine.

**Additional context**
I am sure that just like Tasker's "BT Near" state, there is some delay in between scans, and that is perfectly fine. But I have to think that this information is available to throw into the `bluetooth_connection` sensor.

Thanks!