Add ability to receive RemoteId info from other vehicles

It could be useful for various reasons to be able to receive the location of other drones that are publishing using a remote id. Some examples are:

- warning the pilot of other drones in the area
- object avoidance of other drones
- automatic monitoring/filming of drones in the area

The issue names no files, tests, or entry points. Start by surveying the repository and its OpenDroneID requirements to determine where Remote ID data from other vehicles should be received. Done means the project can receive and expose other vehicles' locations for the stated use cases, with verification added where the repository's existing patterns indicate.

Written by the indexing model from the issue text.