Use live snap settings in polygon editor and slab actions

packages/editor/src/components/tools/shared/polygon-editor.tsx

@@ -4,6 +4,7 @@ import { useCallback, useEffect, useMemo, useRef, useState } from 'react'
 import { BufferGeometry, Float32BufferAttribute, type Line, type Object3D } from 'three'
 import { EDITOR_LAYER } from '../../../lib/constants'
 import { sfxEmitter } from '../../../lib/sfx-bus'
+import { snapToHalf } from '../item/placement-math'
 
 const Y_OFFSET = 0.02
 
@@ -187,8 +188,8 @@ export const PolygonEditor: React.FC<PolygonEditorProps> = ({
   // Listen to grid:move events to track cursor position
   useEffect(() => {
     const onGridMove = (event: GridEvent) => {
-      const gridX = Math.round(event.localPosition[0] * 2) / 2
-      const gridZ = Math.round(event.localPosition[2] * 2) / 2
+      const gridX = snapToHalf(event.localPosition[0])
+      const gridZ = snapToHalf(event.localPosition[2])
       const newPosition: [number, number] = [gridX, gridZ]
 
       // Play snap sound when cursor moves to a new grid cell during drag

packages/editor/src/components/ui/panels/slab-panel.tsx

@@ -266,9 +266,11 @@ export function SlabPanel() {
           value={node.material}
         />
       </PanelSection>
-      <ActionGroup>
-        <ActionButton icon={<Move className="h-3.5 w-3.5" />} label="Move" onClick={handleMove} />
-      </ActionGroup>
+      <PanelSection title="Actions">
+        <ActionGroup>
+          <ActionButton icon={<Move className="h-3.5 w-3.5" />} label="Move" onClick={handleMove} />
+        </ActionGroup>
+      </PanelSection>
     </PanelWrapper>
   )
 }