fix: Prevent layer interactions when not editing

Guard layer selection, cursor, and resize interactions behind
the editing state to avoid unintended modifications in view mode.

src/components/md-deck/hooks/useLayerInteraction.ts

@@ -87,6 +87,8 @@ export function useLayerInteraction(
   const handleLayerClick = (index: number, e: MouseEvent) => {
     e.stopPropagation();
 
+    if (!store.state.isEditing || store.state.fixed) return;
+
     const currentlySelected = store.state.selectedLayer;
 
     if (currentlySelected === index) {
@@ -100,6 +102,7 @@ export function useLayerInteraction(
 
   const handleCardClick = (e: MouseEvent, cardEl: HTMLElement) => {
     if (store.state.draggingState) return;
+    if (!store.state.isEditing || store.state.fixed) return;
 
     const { gridX, gridY } = calculateGridCoords(e, cardEl);
     const overlapping = getOverlappingLayers(gridX, gridY);
@@ -147,6 +150,7 @@ export function useLayerInteraction(
     edge?: "n" | "s" | "e" | "w",
     e?: MouseEvent,
   ) => {
+    if (!store.state.isEditing || store.state.fixed) return;
     if (store.state.selectedLayer === null) return;
     if (e) e.stopPropagation();