Two independent grids, each with a size and a snap toggle: - Garden grid (owner-set, in the garden settings form): drives the editor's visual grid and, when snapping is on, snaps objects on place/move and snaps their dimensions to whole grid steps on resize. - Bed grid (per plantable object, in the bed Inspector): when snapping is on, plants snap to the bed's grid on place/move, and the grid is drawn inside the focused bed. Plant radius stays free. Snapping defaults off on both, so existing gardens keep free placement. Grid spacing shares the [1cm, 100m] range and defaults to 1m (garden) / 30cm (bed); 0 is treated as unset and re-defaulted. Backend: migration 0005 adds grid_size_cm/snap_to_grid to gardens and garden_objects, threaded through domain/store/service/api with service + api round-trip tests. Frontend: new geometry snap helpers (unit-tested), schema/type plumbing, canvas + overlay snapping, and the two forms. Co-Authored-By: Claude Opus 4.8 (1M context) <[email protected]> Claude-Session: https://claude.ai/code/session_01JdQpdYYsTgtkJBxbcpAszi