[BUG]: A11y - Content tree caret buttons has no accessible name/role/value

[liamlaverty]

Describe the bug
Caret buttons in the left hand menu have no guidance for accessibility users. This fails WCAG 2.0 & 2.1 rule 4.1.2 - name, role, value

To Reproduce
Steps to reproduce the behavior:

1. Open the typescript app
2. right click the caret next to the recycle bin
3. inspect element
4. see the HTML content excludes an aria-label:

<button id="caret-button">
              <uui-symbol-expand></uui-symbol-expand>
            </button>

Expected behavior

Carets should be updated to include an aria-label which describes the button's action, for example:

<button id="caret-button" aria-label="Reveal child content nodes">
              <uui-symbol-expand></uui-symbol-expand>
            </button>

Screenshots
Screenshot shows where to find a caret in the vite app:

Desktop (please complete the following information):

• OS: macOS Sonoma 14.2.1 (23C71)
• Browser MS Edge
• Version 122.0

Additional context
Add any other context about the problem here.

[github-actions]

Hi there @liamlaverty!

Firstly, a big thank you for raising this issue. Every piece of feedback we receive helps us to make Umbraco better.

We really appreciate your patience while we wait for our team to have a look at this but we wanted to let you know that we see this and share with you the plan for what comes next.

• We'll assess whether this issue relates to something that has already been fixed in a later version of the release that it has been raised for.
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• We'll replicate the issue to ensure that the problem is as described.
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We wish we could work with everyone directly and assess your issue immediately but we're in the fortunate position of having lots of contributions to work with and only a few humans who are able to do it. We are making progress though and in the meantime, we will keep you in the loop and let you know when we have any questions.

Thanks, from your friendly Umbraco GitHub bot 🤖 🙂