Allow many to many relationship between officers & radios

[AetherUnbound]

We have found that officers can have more than one radio, and radios can be assigned to more than one officer. We will need to alter the relationship on the DB level, but then alter how responses are returned by the API. Several downstream services are expecting only one officer per radio, so this may affect said services.

We should probably have multiple endpoints, one that returns just one officer (the current implementation) and another that returns all known officers. We will then need to figure out how to determine the "one" officer to show - should it be the most recently or least recently updated officer record?