chore: Exposes internal dependencies for chart components

[pan-kot]

Description

Fixes small issues and exposes internal components to be consumed by new chart components (cloudscape-design/chart-components#2).

How has this been tested?

• New unit tests
• Screenshot tests

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

Attention: Patch coverage is 96.66667% with 1 line in your changes missing coverage. Please review.

Project coverage is 96.49%. Comparing base (dddd3f5) to head (5858cdb).
Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
src/popover/use-popover-position.ts	85.71%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #3333      +/-   ##
==========================================
- Coverage   96.49%   96.49%   -0.01%     
==========================================
  Files         807      806       -1     
  Lines       23066    23079      +13     
  Branches     7908     7564     -344     
==========================================
+ Hits        22258    22270      +12     
- Misses        754      802      +48     
+ Partials       54        7      -47     

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[pan-kot]

The awsui-screenreader-text class name is used to locate the part of the expandable section to get extracted for screenreader announcement. It it used in the series-detail-text util. The same approach is to be reused in the chart-components, where we can't use the hashed internal class name.

[jperals]

Can we solve this alternatively by extracting a selector with this class to a scss file to be added to the internal/do-not-use directory?

This is an approach we are already using, and we would avoid customers using this class name directly.