fix: Keyboard Tab navigation in settings modal

[Nishthajain7]

Issue:

Fixes #4070

Demo:

Screencast.from.2026-04-10.13-13-11.webm

Changes:

• Implemented a proper focus trap to control Tab navigation within the modal
• Ensured focus moves only through visible and relevant elements
• Fixed navigation so it no longer gets stuck within toggle buttons
• Included links and all interactive elements in the tab order
• Improved modal accessibility behavior to align with expected keyboard navigation

I have verified that this pull request:

• has no linting errors (npm run lint)
• has no test errors (npm run test)
• has no typecheck errors (npm run typecheck)
• is from a uniquely-named feature branch and is up to date with the develop branch.
• is descriptively named and links to an issue number, i.e. Fixes #123
• meets the standards outlined in the accessibility guidelines