Toggle the theme on pressing the enter key

[arbirali]

Description

This pull request resolves several accessibility issues in the Tutor Indigo theme that were identified during a recent accessibility review. These updates aim to improve usability for all users, especially those relying on assistive technologies. The changes also help ensure compliance with recognized accessibility standards, such as the Web Content Accessibility Guidelines (WCAG) 2.1.

For further details, please refer to the related issue: overhangio/tutor-indigo#146.

Accessibility Fixes Implemented

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Focus on the Theme Toggle Button

The theme toggle button lacked a visible focus indicator for keyboard users. This has been addressed by ensuring a clear focus style is applied.

• Issue: Taiga - US/139
• Live Example: Home Page
• Linked Pull Requests: Brand Openedx - Tutor Indigo

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Theme Toggle Button Does Not Have an Accessible Name

The theme toggle button previously lacked an accessible name, which made it unclear to screen reader users. This update adds a title attribute with the value "Toggle Theme" to ensure assistive technologies can properly identify the button's purpose.

• Issue: Taiga - US/95
• Live Example: Home Page

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Accessibility Audit Report

For the full audit and issue breakdown, please refer to the following report:
Accessibility Audit - Taiga US/111

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 68.39%. Comparing base (fedab6c) to head (645957b).
Report is 1 commits behind head on sumac/indigo.

Additional details and impacted files

@@               Coverage Diff                @@
##           sumac/indigo      #27      +/-   ##
================================================
+ Coverage         64.77%   68.39%   +3.61%     
================================================
  Files                49       49              
  Lines               477      481       +4     
  Branches            105      106       +1     
================================================
+ Hits                309      329      +20     
+ Misses              165      149      -16     
  Partials              3        3              

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