[UIK-3324] header controls

[sheila-semrush]

Motivation and Context

This is a draft.

If you decide to work on it before my return, here's what requires attention:

1. Decide what to do with header control tokens. There are different ways, and for some of them we need to make changes in our theme processor. Details are in vars.css.
2. Decide how to organize the new styles - make a package with wrappers like currently in the PR, or something different.
3. Bug in Select: SHeaderButtonTrigger class isn't applied to trigger (HeaderButtonTrigger itself is styled correctly though), I broke something when copying Select wrapper from Feature highlight.

What is still needed from design:

1. Fix some style values, some colors are not correct right now.
2. Add styles for ButtonTrigger states.

How has this been tested?

Screenshots (if appropriate):

Types of changes

• Bug fix (non-breaking change which fixes an issue).
• New feature (non-breaking change which adds functionality).
• Breaking change (fix or feature that would cause existing functionality to not work as expected).
• Nice improve.

Checklist:

• I have updated the documentation accordingly.
• I have added changelog note to corresponding CHANGELOG.md file with planned publish date.
• I have added new tests on added of fixed functionality.