AI workflow assistance adds undo, voice input, and safer edits

The AI workflow assistant now gives builders more control during longer workflow-building sessions and safer recovery when a change needs to be reversed.

• Stop in-progress assistant responses when needed.
• Dictate prompts with voice input or use keyboard shortcuts to move through assistant actions.
• Preview and undo recent assistant changes.
• Ask the assistant to summarize workflow structure as YAML, JSON, tables, diagrams, or PDFs.
• Apply mapped values, schedules, retry settings, notifications, and Map step edits more consistently.