UIK-3013/date picker tests

[Valeria-Zimnitskaya]

This is quite a complex component, so I divided the browser tests by component type:

• Date Picker
• Date Range Picker
• Date Range Comparator
• Month Picker
• Month Range Picker
• Month Range Comparator

Each browser test includes checks for roles and attributes, styles, input behavior, keyboard and mouse interactions, and props handling.

I also added more test stories to cover various states and props.
There are many snapshots, but they don’t duplicate each other — each snapshot focuses on different functionality (some check additional focus states, others check hover or specific props).

So despite the large number of tests, they provide good coverage of the component without redundancy and help prevent regressions.

I also added axe tests and removed almost all snapshots from unit tests, I left just a few to maintain some visual variability.

150 tests run ~2m

Motivation and Context

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:

• My code follows the code style of this project.
• I have updated the documentation accordingly or it's not required.
• Unit tests are not broken.
• I have added changelog note to corresponding CHANGELOG.md file with planned publish date.
• I have added new unit tests on added of fixed functionality.