Run an accessibility review across all AI Experiments UI and editor integrations, addressing any issues found. Where possible, introduce automated accessibility checks into CI to prevent regressions.

This work should cover experiment settings screens, editor UI elements, modals, buttons, and messaging related to AI provider configuration.

Acceptance criteria:

• Manual accessibility review completed for all current experiments and settings screens
• Identified a11y issues are fixed or documented with follow-up issues
• Basic automated accessibility checks added to CI (where feasible)
• No critical accessibility issues remain for 1.0.0