bdde03cdfa
- Resize handles only render when the plan is selected (click to select, click outside to deselect); previously always shown when unlocked. - Double-clicking an unlocked plan opens the canvas edit modal (via a floorMapEditNonce signal the Sidebar watches). - Floor plan always sits at the bottom of the canvas (z-index -1), behind nodes and edges, locked or not. - Remount the edit modal on every open (key bump) so it re-seeds from the current floor plan; fixes Save clobbering a canvas-side resize/move with stale modal dimensions. - Drop the no-op history snapshot on floor-plan edits (floorMap isn't part of undo history).