Feature: Adapt class

[Davknapp]

Closes #2046

This is a draft PR for an outline (and hopefully later on meant seriously) adapt class.

It provides a class that manages the adaptation of a forest. The adaption is split into several parts:

• the gathering of the adaptation action via element-callbacks
• the family check
• the execution of the action matching the results of the element-callbacks and the are_family checks.

The goal is to provide a general functionality of adaptivy whilst also providing the flexibilty to speciallize for other adaptions, like forests with wholes, or subelements. The steps can be overwritten to provide such functionality and also to create new adaptions workflows more easily.

Please feel free to discuss it in this draft PR.

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