[Linux] CA state parsing, robuster handshake, persistent window

[tim-gromeyer]

This PR adds following features:

• Parse Conversational Awareness state from the AirPods (instead of storing it locally)
• Don't quit the app when we close the window
• Extract MagicAccIRK and MagicAccEncKey
• Add ability to disable cross-device (you need to manually edit the config file for now)
• More robust handshake, notification request