Workflow editor canvas navigation for large workflows

The workflow editor canvas now handles large workflows with smoother navigation and clearer step controls.

• Pan, zoom, and reset the workflow canvas.
• Use keyboard shortcuts for common workflow actions.
• Work with color-coded step categories, clearer trigger badges, and add-step-before controls.
• Navigate large workflows more smoothly with virtualized canvas steps.
• Drag, select, comment, and collapse steps more predictably.