[Controls] Allow the control type to be changed when editing existing control

[Heenawter]

Follow up to #127524

Describe the feature:

When creating a new control, users are able to select one of many possible control types:

However, when editing an existing control, users are only given the option for the type of control that is being edited.

Ideally, the same options should be present for both menus - however, this requires the ability to replace the control embeddable with one of a different type.

[elasticmachine]

Pinging @elastic/kibana-presentation (Team:Presentation)

[teresaalvarezsoler]

@Heenawter IMO, the ideal solution would be to allow the user to freely choose another type and another field. However, if this makes things more complex, a quick solution may be to show the other type of control icon disabled. What do you think?

[Heenawter]

@teresaalvarezsoler Yeah, the field part would naturally be part of this - that hard part is the type switching, not the field switching :) I talked with @andreadelrio about it, and we agreed to avoid disabling certain options, hence why you only see the current type when editing an existing control for now. We should only show the other options once we support switching types