[devtools] Accessibility

[aacebo]

add accessibility for keyboard navigation and other such things.

• Chat focus (arrows between chat messages)
• MessageActionToolbar - focus via tab includes added reactions; arrows cycle through actual toolbar
• Notification center
• a11y fastpass
• quick assess
• tab order check
• JSON view in ActivitiesScreen does not meet contrast requirements
• jest-axe
• ChatMessagesContainer: Ensure we're using appropriate date-format methods for tooltip content
  // to maintain consistent date formatting across the application and handle
  // timezone differences properly