Replace in-/output properties with signals

[Matthbo]

@Input() ... and @Output() ... should be replaced with the new signals system.
E.g.

// @Input({ ... }) active = ...;
public active = input<...>(...);

// @Output() activeChange = new EventEmitter<...>();
public activeChange = output<...>();

This means parents do need to handle input and output fully.
To follow the example above, activeChange will output a change in state and the parent has to update the active input to reflect the state change or else to component simply wont update. This also means the state is fully managed by the parent instead of having any state internally