DC.121 BimCraft: drag a Library item onto the plan to place it

Owner, 2026-11-09: 'the drag and drop onto plan feature request STILL isn't implemented - this needs to be in 0.9'. The original request was not found in the roadmap, suggestions, docs or memory, so it is built as the owner described it: a Library card dragged onto the plan (Plan view, or the plan half of Split) places the item there through the same place-object process, the drop point being the start position. Dropped files still open as files. Keyboard route: the split Place button.