feat(SVGNav): Enhance nav accessibility
Purpose
Improve both the visual and programmatic indicators of the current page.
- Add navigation landmark.
- Use
selectedclass and `aria-selected="true" for button that relates to the current page.
Note
The recent updates to the SVG Viewer leveraged GitLab UI and Tailwind while trying to avoid custom styles. Along those lines, this uses what's available for indicating a selected button by using the selected class. Although the visual result is probably not what we'd want in a navigation setting, this MR is a first step towards making the navigation more accessible while using currently available styles.
Screenshots
| Before | After |
|---|---|
| CleanShot_2025-04-24_at_08.54.25 | CleanShot_2025-04-24_at_08.55.34 |