geographically limit access to recording feature

[hburgund]

Rather than allowing participants to make recordings anywhere they want, it would be useful to be able to define a geography where making recordings is allowed. Some projects have areas where we want only the pre-composed/added speakers to play without any user-generated content and other areas where user-generated content is encouraged.

This also brings up the question of what should happen when someone tries to make a recording in looping recording mode at a location that does not already have a speaker? Seems like this could make a new "seed" that others can sing along with, but this should be one option and the other option should be to disallow making a recording in looping recording mode when there isn't a "base loop" to sing along with (essentially, meaning no recording feature available unless inside a speaker shape).

Perhaps there are several options for recording availability:

• anywhere (current functionality)
• only inside current speakers (mainly used in looping recording mode)
• only inside defined geography (not sure how to define and store this data, but probably as a new project.recording_availability_shape field in the database?)