👐 a11y: Accessible Conversation Menu Options

[danny-avila]

Summary

Closes #3823
Closes #3788

• Refactored the DropdownPopup component to use Ariakit for improved accessibility and keyboard navigation
• Updated the ConvoOptions component to use Ariakit MenuButton for better accessibility
• Fixed the menu button in the chat history area to properly indicate its state
• Improved keyboard access to chat menus in the chat history
• Updated the styling of the ConvoOptions menu button and NewChat component
• Fixed the document title setting in the Conversation component
• Resolved type issues in the Conversation component
• Updated the z-index values for the ConvoOptions menu button and NewChat component to ensure proper layering

To test these changes:

1. Navigate through the conversation list using both mouse and keyboard
2. Verify that the menu buttons in the chat history are accessible via keyboard
3. Check that the conversation options menu properly indicates its state when opened
4. Ensure that the document title updates correctly when switching conversations
5. Confirm that the UI styling is consistent and the z-index changes resolve any layering issues

Recording.2024-08-30.133546.mp4