Feature/explore lexical

[andresgutgon]

What?

Try Lexical as blocks editor. I tried tiptap but didn't find a way of implementing nested drag & drop. Which is a bit of a shame. Also they have a semi-private system where some plugins are paid. Not sure if want that in this project being open-source.

TODO

• Main blocks and their nesting rules
• Keyboard navigation between blocks
• Editing step label avoid deleting everything and also check if this state is stored in Lexical so can be serialized later
• Editable step name makes lose the keyboard up and down of the cursor for the blocks 🐛
• Drag & drop
• Check how commands work