[FR] Bluetooth collaborative remote control

[nift4]

Is your feature request related to a problem? Please describe.
(Received per E-Mail.) When I'm at a party and play music using a bluetooth speaker, other people may request a song. It'd be nice if they could add a song to queue.

Describe the solution you'd like
Allow Gramophone to connect to another instance of Gramophone via Bluetooth, and then allow to:

• pick out song from host's library to add to queue
• pick out own song which gets streamed to host via Bluetooth in advance to playing to add to queue
• if host user allows it, remove other's songs from queue / skip / play / pause / etc

Describe alternatives you've considered
Use Spotify

Additional context
N/A

• I will open one issue per request, follow the issue format and will add [FR] to the start of my issue title, and I acknowledge that if I don't follow the format, my issue might get closed without further explanation.