test: Add visual regression tests for app layout

[jperals]

Description

Migrate all app layout visual regression tests to the new test definitions.

Related ticket: D417180663

How has this been tested?

Manually verified that all visual regression tests executed in the internal pipeline were also run in this PR's checks (see Allure report).

Also manually verified the screenshots for some of them.

Review checklist

The following items are to be evaluated by the author(s) and the reviewer(s).

Correctness

• Changes include appropriate documentation updates.
• Changes are backward-compatible if not indicated, see CONTRIBUTING.md.
• Changes do not include unsupported browser features, see CONTRIBUTING.md.
• Changes were manually tested for accessibility, see accessibility guidelines.

Security

• If the code handles URLs: all URLs are validated through the checkSafeUrl function.

Testing

• Changes are covered with new/existing unit tests?
• Changes are covered with new/existing integration tests?

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 97.60%. Comparing base (58313f2) to head (b5219ec).

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #4714   +/-   ##
=======================================
  Coverage   97.60%   97.60%           
=======================================
  Files         950      950           
  Lines       30714    30714           
  Branches    11275    11276    +1     
=======================================
  Hits        29977    29977           
+ Misses        730      690   -40     
- Partials        7       47   +40     

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[jperals]

Note: this test description in the internal package is called "with tooltip on hover in visual refresh", but the test is run for all systems and themes without distinction, including Classic , so I am dropping the "in visual refresh" part (which is not the special case anymore anyway)