Provide API endpoint to query CBA media details

Parent: [Epic] CBA Media URL Resolver (aura#440 - closed)

Read-only endpoint for example via /cba/media proxying the response from the same CBA endpoint, using the CBA API key provided by the station settings (aura#221 (closed)). Additionally CBA domains can be used as a basis for validating a valid CBA base URL.

There are existing JS and PHP implementations, where @david can provide more details. Also dashboard#176 (closed) provides relevant details on the request details.

This is the basis for dashboard#176 (closed).

Dependencies

• [EPIC] Basic radio station administration (aura#221 - closed)