chore: Replace one-theme’s side navigation icon

[georgylobko]

Description

Replaced existing side navigation icon in AppLayout when one-theme is applied.

Screen.Recording.2026-09-02.at.2.01.56.PM.mov

Related links, issue #, if available: n/a

How has this been tested?

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 97.66%. Comparing base (dec0201) to head (903ff58).

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #4963   +/-   ##
=======================================
  Coverage   97.66%   97.66%           
=======================================
  Files         959      959           
  Lines       31342    31347    +5     
  Branches    11577    11579    +2     
=======================================
+ Hits        30611    30616    +5     
  Misses        724      724           
  Partials        7        7           

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[jkuelz]

Let's also make it only when collapsible={true} for now. This will help set expectations, and also improve consistency with the way other drawers behave, given that we aren't changing the icon for drawers that collapse fully.

[georgylobko]

Addressed