Left/Right Arrow Keys Navigation

[rs545837]

The issue for the left navigation from the help menu to the userlist toggle button is working with this PR. Although there is still an issue on using the right arrow key to navigate from the same toggle button to the help menu, even when the logic of the code seems to be correct.
Still working on resolving it.

Fixes: #29465.

Screenshots and screen captures:

Self-review checklist

• Self-reviewed the changes for clarity and maintainability
  (variable names, code reuse, readability, etc.).

Communicate decisions, questions, and potential concerns.

• Explains differences from previous plans (e.g., issue description).
• Highlights technical choices and bugs encountered.
• Calls out remaining decisions and concerns.
• Automated tests verify logic where appropriate.

Individual commits are ready for review (see commit discipline).

• Each commit is a coherent idea.
• Commit message(s) explain reasoning and motivation for changes.

Completed manual review and testing of the following:

• Visual appearance of the changes.
• Responsiveness and internationalization.
• Strings and tooltips.
• End-to-end functionality of buttons, interactions and flows.
• Corner cases, error conditions, and easily imagined bugs.

[timabbott]

@rs545837 can you clean up the commented-out print statements?

[alya]

I will hold off on next steps for reviewing this PR until the right arrow works as well.

[rs545837]

Hey @alya, should I go for a new PR for a cleaner commit history? I actually did make a new cleaner PR #29781.

[alya]

Closing in favor of #29781. But next time, please push your changes to the same PR, rather than starting a new one.