[QA-04] Accessibility audit — achieve WCAG 2.1 AA compliance across all main pages

[yusuftomilola]

Overview

AssetsUp is used by operations teams in enterprise environments, which may include users with disabilities. Web accessibility is also a legal requirement in many jurisdictions. This issue audits the current UI for WCAG 2.1 AA violations and fixes the highest-impact issues.

Context

• Run automated audits using axe-core (via @axe-core/playwright in Playwright tests or the browser extension)
• Priority pages: Login, Dashboard, Asset List, Asset Detail, Settings
• Key WCAG 2.1 AA criteria to check: colour contrast (4.5:1 for normal text), keyboard navigability, focus indicators, ARIA labels on icon-only buttons, alt text on images, form labels

Acceptance Criteria

• Run axe-core audit on the 5 priority pages and document all violations with severity and affected element
• Fix all "critical" and "serious" axe violations before closing this issue
• Ensure all interactive elements (buttons, links, form inputs) are reachable and operable via keyboard alone (Tab, Shift+Tab, Enter, Space, arrow keys)
• Add visible focus rings to all interactive elements (override any outline: none in global CSS)
• Add aria-label to all icon-only buttons (e.g., delete, edit, close modal buttons)
• Verify colour contrast on status badges, charts, and alert banners — update colours where contrast is insufficient
• Add alt text to all images (asset photos, avatars, QR codes)
• Add an axe-playwright test to QA-01's test suite that fails if new critical violations are introduced