Photo assistant: full product range in the template and copying a variant

The template for stable and yard now covers the full product range: single parts such as gates, drinkers and brushes, runs and fences, yard and garden with recycled plastic products, plus gates, windows and ventilation, with rules for plausible heights and orientations. If the user leaves the choice open, the assistant suggests matching products from the catalog and explains them; products can be named directly. New is "Copy variant": a good variant stays as it is, the copy starts from its current version without rendering again and can be changed right away.