fix: emit layout change for batch node bounds (#5939)

## Summary

Fixes issue where node size changes are not serialized by routing
DOM-driven node bounds updates through a single CRDT operation so Vue
node geometry stays synchronized with LiteGraph.

## Changes

- **What**: Added `BatchUpdateBoundsOperation` to the layout store,
applied it via the existing Yjs pipeline, notified link sync to
recompute touched nodes, and covered the path with a regression test

## Review Focus

Correctness of the new batch operation when multiple nodes update
simultaneously, especially remote replay/undo scenarios and link
geometry recomputation.

┆Issue is synchronized with this [Notion
page](https://www.notion.so/PR-5939-fix-emit-layout-change-for-batch-node-bounds-2846d73d365081db8f8cca5bf7b85308)
by [Unito](https://www.unito.io)

---------

Co-authored-by: github-actions <github-actions@github.com>

src/renderer/core/layout/store/layoutStore.ts

@@ -12,6 +12,7 @@ import * as Y from 'yjs'
 import { ACTOR_CONFIG } from '@/renderer/core/layout/constants'
 import { LayoutSource } from '@/renderer/core/layout/types'
 import type {
+  BatchUpdateBoundsOperation,
   Bounds,
   CreateLinkOperation,
   CreateNodeOperation,
@@ -871,6 +872,12 @@ class LayoutStoreImpl implements LayoutStore {
       case 'deleteNode':
         this.handleDeleteNode(operation as DeleteNodeOperation, change)
         break
+      case 'batchUpdateBounds':
+        this.handleBatchUpdateBounds(
+          operation as BatchUpdateBoundsOperation,
+          change
+        )
+        break
       case 'createLink':
         this.handleCreateLink(operation as CreateLinkOperation, change)
         break
@@ -1099,6 +1106,38 @@ class LayoutStoreImpl implements LayoutStore {
     change.nodeIds.push(operation.nodeId)
   }
 
+  private handleBatchUpdateBounds(
+    operation: BatchUpdateBoundsOperation,
+    change: LayoutChange
+  ): void {
+    const spatialUpdates: Array<{ nodeId: NodeId; bounds: Bounds }> = []
+
+    for (const nodeId of operation.nodeIds) {
+      const data = operation.bounds[nodeId]
+      const ynode = this.ynodes.get(nodeId)
+      if (!ynode || !data) continue
+
+      ynode.set('position', { x: data.bounds.x, y: data.bounds.y })
+      ynode.set('size', {
+        width: data.bounds.width,
+        height: data.bounds.height
+      })
+      ynode.set('bounds', data.bounds)
+
+      spatialUpdates.push({ nodeId, bounds: data.bounds })
+      change.nodeIds.push(nodeId)
+    }
+
+    // Batch update spatial index for better performance
+    if (spatialUpdates.length > 0) {
+      this.spatialIndex.batchUpdate(spatialUpdates)
+    }
+
+    if (change.nodeIds.length) {
+      change.type = 'update'
+    }
+  }
+
   private handleCreateLink(
     operation: CreateLinkOperation,
     change: LayoutChange
@@ -1379,19 +1418,38 @@ class LayoutStoreImpl implements LayoutStore {
     const originalSource = this.currentSource
     this.currentSource = LayoutSource.Vue
 
-    this.ydoc.transact(() => {
-      for (const { nodeId, bounds } of updates) {
-        const ynode = this.ynodes.get(nodeId)
-        if (!ynode) continue
+    const nodeIds: NodeId[] = []
+    const boundsRecord: BatchUpdateBoundsOperation['bounds'] = {}
 
-        this.spatialIndex.update(nodeId, bounds)
-        ynode.set('bounds', bounds)
-        ynode.set('position', { x: bounds.x, y: bounds.y })
-        ynode.set('size', { width: bounds.width, height: bounds.height })
+    for (const { nodeId, bounds } of updates) {
+      const ynode = this.ynodes.get(nodeId)
+      if (!ynode) continue
+      const currentLayout = yNodeToLayout(ynode)
+
+      boundsRecord[nodeId] = {
+        bounds,
+        previousBounds: currentLayout.bounds
       }
-    }, this.currentActor)
+      nodeIds.push(nodeId)
+    }
+
+    if (!nodeIds.length) {
+      this.currentSource = originalSource
+      return
+    }
+
+    const operation: BatchUpdateBoundsOperation = {
+      type: 'batchUpdateBounds',
+      entity: 'node',
+      nodeIds,
+      bounds: boundsRecord,
+      timestamp: Date.now(),
+      source: this.currentSource,
+      actor: this.currentActor
+    }
+
+    this.applyOperation(operation)
 
-    // Restore original source
     this.currentSource = originalSource
   }
 }

src/renderer/core/layout/sync/useLinkLayoutSync.ts

@@ -267,6 +267,11 @@ export function useLinkLayoutSync() {
           case 'resizeNode':
             recomputeLinksForNode(parseInt(change.operation.nodeId))
             break
+          case 'batchUpdateBounds':
+            for (const nodeId of change.operation.nodeIds) {
+              recomputeLinksForNode(parseInt(nodeId))
+            }
+            break
           case 'createLink':
             recomputeLinkById(change.operation.linkId)
             break

src/renderer/core/layout/types.ts

@@ -122,7 +122,7 @@ type OperationType =
   | 'createNode'
   | 'deleteNode'
   | 'setNodeVisibility'
-  | 'batchUpdate'
+  | 'batchUpdateBounds'
   | 'createLink'
   | 'deleteLink'
   | 'createReroute'
@@ -184,10 +184,11 @@ interface SetNodeVisibilityOperation extends NodeOpBase {
 /**
  * Batch update operation for atomic multi-property changes
  */
-interface BatchUpdateOperation extends NodeOpBase {
-  type: 'batchUpdate'
-  updates: Partial<NodeLayout>
-  previousValues: Partial<NodeLayout>
+export interface BatchUpdateBoundsOperation extends OperationMeta {
+  entity: 'node'
+  type: 'batchUpdateBounds'
+  nodeIds: NodeId[]
+  bounds: Record<NodeId, { bounds: Bounds; previousBounds: Bounds }>
 }
 
 /**
@@ -244,7 +245,7 @@ export type LayoutOperation =
   | CreateNodeOperation
   | DeleteNodeOperation
   | SetNodeVisibilityOperation
-  | BatchUpdateOperation
+  | BatchUpdateBoundsOperation
   | CreateLinkOperation
   | DeleteLinkOperation
   | CreateRerouteOperation

src/renderer/core/spatial/SpatialIndex.ts

@@ -55,6 +55,17 @@ export class SpatialIndexManager {
     this.invalidateCache()
   }
 
+  /**
+   * Batch update multiple nodes' bounds in the spatial index
+   * More efficient than calling update() multiple times as it only invalidates cache once
+   */
+  batchUpdate(updates: Array<{ nodeId: NodeId; bounds: Bounds }>): void {
+    for (const { nodeId, bounds } of updates) {
+      this.quadTree.update(nodeId, bounds)
+    }
+    this.invalidateCache()
+  }
+
   /**
    * Remove a node from the spatial index
    */