Custom shape SVG export

Determine how your custom shapes look when copied/exported as an image.

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The "export as SVG/PNG" and "copy as SVG/PNG" actions use the toSvg or toBackgroundSvg methods of a shape util. If a shape does not have a toSvg or toBackgroundSvg method defined, it will default to placing the shape's component inside a <foreignObject> element.