Improve copier questions and behavior on update

[dalito]

The cookiecutter-related hooks directory can be removed. The scripts contain validation logic and post-setup messages. Both can be replaced by standard options in copier.yaml.

Copier allows to ask questions based on conditions. This can be used to ask less, for example if use_schemasheets is answered with "No" all related questions on details can be skipped.

On update but also when switching a project created with linkml-project-cookiecutter to this template, less files should be changed/overwritten. Limiting changes on update is possible to some extend now but will probably further improve, see copier-org/copier#1733.

[dalito]

In order to make the template more useful for providing continuous, easy-to-merge updates to the derived projects, the template needs to be partially re-designed. This will break compatibility with the linkml-project-cookiecutter template and is not planned for 0.1.x releases/tags.