Phase 5.3 -- Accessibility & Keyboard Navigation

Parent: #762

Context

Design principle #7: "Keyboard-first." Radix UI provides accessibility primitives but we need to verify the full experience.

Scope

Keyboard Navigation

• Cmd+K reachable from everywhere
• Arrow keys navigate lists (agent list, task board, approval list, settings)
• Enter opens detail, Escape closes panels/dialogs
• Tab order logical on every page
• Focus visible indicators (not browser default -- styled to match design system)

Screen Reader

• ARIA labels on all interactive elements
• ARIA live regions for real-time updates (activity feed, status changes)
• Meaningful alt text for charts/visualizations
• Landmark roles for page sections

Color & Contrast

• Verify WCAG AA compliance end-to-end (not just tokens, but actual rendered UI)
• Status information not conveyed by color alone (shape + label + color)
• Focus indicators have sufficient contrast

Testing

• Storybook a11y addon audit (all stories)
• Manual screen reader testing (NVDA/VoiceOver)
• Keyboard-only navigation test through all pages

Deliverables

• All keyboard navigation patterns working
• ARIA labels and live regions
• Storybook a11y audit passing
• Screen reader tested
• Focus management verified on all pages
• Status encoding uses shape + label + color (not color alone)

Blocked by

• Phase 4 pages substantially complete