A11y Improve navigation and structural elements

[adamwhitlock1]

User Story

As a user of the application, I need accessible navigation and properly structured content.

Background

We identified several issues related to navigation, heading structure, and ARIA labeling.

ACs

• [x] Add a unique aria-label to the tab bar navigation to distinguish it from other navigation elements
• [x] Correct heading levels to ensure they increase by only one level at a time and heading hierarchy makes sense
• [x] Change the title of the form to remove "AE" to make it understandable for screen readers
• [x] Evaluate the use of buttons vs. links for task actions on session landing pages, considering VADS guidelines
• [x] Ensure all landmarks have unique roles or accessible names to make them distinguishable

Review needed by

• [ ] VA Product Owner
• [ ] Product Manager
• [ ] UX Research Team
• [ ] Engineering Team

Definition of Done

• [ ] Reviewers have approved.
• [ ] Changes have been tested with various assistive technologies and browsers
• [ ] Navigation structure passes accessibility audits (e.g., aXe, WAVE)
• [ ] Heading structure is semantically correct and follows best practices