Enum values

Added support for defining enum values for enum data types. Also updated the exporter to include these enum values for all export formats.

🌟 Improvements and Fixes

• Show icon on hover columns, to make it clearer visually that columns can be reordered by dragging

• Revamped tooltips in canvas editor v2 to trigger on click instead of hover

• Visual update of the column attribute tooltip, with a more succinct layout, and to show the new enum values