[Feature Request] Allow for in-sim adjustment of radio volume, and switch of Tx/Rx via plane radio stack

I primarily fly X-Plane 12, and xPilot does this through monitoring radio-related datarefs that get modified by pilot input on aircraft radio stacks.

I am not a developer, so I am not aware of which specific datarefs are being monitored by xpilot, but it would be cool to see this get implemented in Swift as an attempt to bring feature parity with other VATSIM pilot clients.