Draft: Display operating principles in the right-side navigation menu

Why is this change being made?

We display the operating principles in the right-side navigation menu. This makes it easier to find the operating principles and learn which principles support what value.

Current issue: the menu becomes very tall. To solve that I have requested the implementation of foldable menus (Foldable navigational menus (#14488))

before	after

Collaterally, this could help organising the principles in a better way. For example, Say sorry and Say thanks should probably be one after the other, or feedback related principles should be sequentially listed:

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