fix(devices): API to disable speaking while muted notifications

[oliverlaz]

Overview

A joint PR that fixes a couple of related issues:

• Adds an API that disables speaking while muted notifications - fixes Disable microphone while muted #1329
• The selected device can't be reliably detected when audio or video filters are used
• Audio tracks are now stopped (instead of disabled) on the Web - this should release the mic allocation
• Fixed an issue in usePersistedDevicePreferences() where the camera and mic were automatically enabled after a call had been left
• Pronto and Video Demo now remember the last used video filter and they enable it automatically

[oliverlaz]

@szuperaz, we should check if this makes sense once you are back. This defaulted to disable-tracks for the mic, and stop-tracks for the camera. I don't know the reasons behind this.

I tested with Web, and now the mic indicator goes away once both, mic and speaking-while-muted notifications are disabled. I left the previous default for React Native.