fix: prevent unrelated groups from moving when dragging nodes in vueNodes mode (#7473)

## Summary

Previously, when dragging a node that was not part of the selection, any
selected groups would still move along with it. This fix ensures groups
only move when the dragged node is actually part of the selection.

## Screenshots (if applicable)
before


https://github.com/user-attachments/assets/ff9a18c2-59b2-4bbd-81b4-7a6ecb35e659


after


https://github.com/user-attachments/assets/019a6cc6-b1e2-41d1-bfec-d6af7ae84091

┆Issue is synchronized with this [Notion
page](https://www.notion.so/PR-7473-fix-prevent-unrelated-groups-from-moving-when-dragging-nodes-in-vueNodes-mode-2c96d73d365081a194a6fef57f9c1108)
by [Unito](https://www.unito.io)

src/renderer/extensions/vueNodes/layout/useNodeDrag.ts

@@ -57,7 +57,10 @@ function useNodeDragIndividual() {
     const selectedNodes = toValue(selectedNodeIds)
 
     // capture the starting positions of all other selected nodes
-    if (selectedNodes?.has(nodeId) && selectedNodes.size > 1) {
+    // Only move other selected items if the dragged node is part of the selection
+    const isDraggedNodeInSelection = selectedNodes?.has(nodeId)
+
+    if (isDraggedNodeInSelection && selectedNodes.size > 1) {
       otherSelectedNodesStartPositions = new Map()
 
       for (const id of selectedNodes) {
@@ -73,9 +76,15 @@ function useNodeDragIndividual() {
       otherSelectedNodesStartPositions = null
     }
 
-    // Capture selected groups (filter from selectedItems which only contains selected items)
-    selectedGroups = toValue(selectedItems).filter(isLGraphGroup)
-    lastCanvasDelta = { x: 0, y: 0 }
+    // Capture selected groups only if the dragged node is part of the selection
+    // This prevents groups from moving when dragging an unrelated node
+    if (isDraggedNodeInSelection) {
+      selectedGroups = toValue(selectedItems).filter(isLGraphGroup)
+      lastCanvasDelta = { x: 0, y: 0 }
+    } else {
+      selectedGroups = null
+      lastCanvasDelta = null
+    }
 
     mutations.setSource(LayoutSource.Vue)
   }