Rethink WiFi API

[bjoernQ]

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Pull Request Details 📖

Description

This is a POC to address #2224

The idea is

• network devices / interfaces are independent of the controller - they exist before creating the controller and still exist when the controller is dropped
• no type-state for the enabled wifi mode - a user can switch the wifi mode at any time

This might or might not end up being merged. For now, it's here to illustrate how the API can or should be changed

Testing

Run the examples

[bugadani]

This can also be swap or fetch_or, which only need a single Ordering and end up in general simpler. In general I don't know if I'm happy with the interface being a completely separate singleton (or singleton pair) - but at the very least, we need an unsafe way to grab them in case they need to be re-created for some reasn.