[META] Define strategy for keyboard shortcuts

Layout Paragraphs allows moving a layout section or component via keyboard shorctuts:

1. Focus the "move" link in the section or component's floating toolbar using the browser default: click it, or tab/option-tab to it then press enter. The move tooltip is revealed.
2. Use the arrow up/left and down/right keys to move the item.
3. Click return or tab to accept the move, or escape to cancel. The tooltip is hidden.

To keep in mind:
- avoid conflicts with users accessibility technology (https://www.w3.org/WAI/WCAG21/Understanding/character-key-shortcuts)
- about navigating grids, includes examples of common keys (https://www.w3.org/WAI/ARIA/apg/patterns/grid/#keyboardinteraction-setti...)
- navigation matching html-element and visual (eg. no radio-button grids with directional arrows, if non-visually only prev-next)

It looks like Wix doesn't have a full keyboard support, since some shortcuts say fe. "while dragging" https://support.wix.com/en/article/wix-editor-keyboard-shortcuts-in-the-...

This page includes Wordpress shortcuts for Gutenberg https://www.zettahost.com/wordpress-tutorials/gutenberg-keyboard-shortcuts/