fix: inner groups being moved double when moving outer group (in vue mode) (#7447)

## Summary

Fixes issue when dragging a group that had inner groups when in vue
mode.

When dragging the outer group in Vue mode:

1. getAllNestedItems(selected) returns ALL items: outer group + inner
groups + nodes
2. moveChildNodesInGroupVueMode loops through all items
3. For outer group G1: calls G1.move(delta, true) then
moveGroupChildren(G1, ...)
4. moveGroupChildren calls G2.move(delta) (no skipChildren) - this moves
G2 AND G2's children!
5. Then the loop reaches G2: calls G2.move(delta, true) - moves G2 again
6. Plus moveGroupChildren(G2, ...) processes G2's children again

This PR fixes it by adding `skipChildren=true` to the `move` call.

┆Issue is synchronized with this [Notion
page](https://www.notion.so/PR-7447-fix-inner-groups-being-moved-double-when-moving-outer-group-in-vue-mode-2c86d73d365081ce97abec682f2a8518)
by [Unito](https://www.unito.io)

src/lib/litegraph/src/LGraphCanvas.ts

@@ -8564,9 +8564,11 @@ export class LGraphCanvas implements CustomEventDispatcher<LGraphCanvasEventMap>
           node,
           newPos: this.calculateNewPosition(node, deltaX, deltaY)
         })
-      } else {
-        // Non-node children (nested groups, reroutes)
-        child.move(deltaX, deltaY)
+      } else if (!(child instanceof LGraphGroup)) {
+        // Non-node, non-group children (reroutes, etc.)
+        // Skip groups here - they're already in allItems and will be
+        // processed in the main loop of moveChildNodesInGroupVueMode
+        child.move(deltaX, deltaY, true)
       }
     }
   }