A11y fable/lexical prototype

[andrewleith]

Summary | Résumé

PR to create a prototype for lexical for fable testing. This prototype enhances the current implementation, adding a few extra a11y features:

• Tooltips/aria-label's on the toolbar items
• Keyboard-specific instructions for screen-reader users:
  • When focus lands on the toolbar it will say:

    • Template toolbar: press the left and right arrow keys to see the formatting options; press tab to enter the content area

  • When focus lands on the content area it will say:

    • Content editor: edit or create your content here. To apply formatting, the desired text and press shift+tab to return to the toolbar and select an option. You can also use markdown formatting directly in the editor.