perf: delete the layout operation log

Every layout operation appended to a Y.Array that nothing ever read.
`getOperationsSince` and `getOperationsByActor` were not on the LayoutStore
interface and had no callers outside the one test that exercised the log
itself; both were marked as being for a future sync feature that no provider
exists for.

It was not free. The array is never trimmed, so per-operation cost grew with
session length. Measured on `moveNode` with an entry present: 197 us/op with
22k entries logged, 375 us/op at 40k. Without the log, 5.4 us/op and flat
(2.9 us/op after another 18k operations) — the growth disappears with it.

This is a live cost in Vue nodes mode today, on every drag frame and every
resize, and it is what made registering node geometry at attach look
unaffordable for the legacy canvas: dragging 100 selected nodes went from
10.8 ms/frame (65% of a 16.7ms frame) to 0.60 ms/frame (3.6%).

The store's test helper observed operations through the log; it spies on
applyOperation instead, which is what nodeSizeReflow.test.ts already did.

Author: DrJKL

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

@@ -20,9 +20,13 @@ import type {
 } from '@/renderer/core/layout/types'
 
 function getOperationsAddedBy(action: () => void): LayoutOperation[] {
-  const operationCount = layoutStore.getOperationsSince(0).length
-  action()
-  return layoutStore.getOperationsSince(0).slice(operationCount)
+  const applySpy = vi.spyOn(layoutStore, 'applyOperation')
+  try {
+    action()
+    return applySpy.mock.calls.map(([operation]) => operation)
+  } finally {
+    applySpy.mockRestore()
+  }
 }
 
 function expectSingleOperation(
@@ -470,45 +474,6 @@ describe('layoutStore CRDT operations', () => {
     expect(nodesInBounds).toContain('node-c')
   })
 
-  it('should maintain operation history', () => {
-    const nodeId = toNodeId('test-node-history')
-    const layout = createTestNode(nodeId)
-    const startTime = Date.now()
-
-    // Create node
-    layoutStore.applyOperation({
-      type: 'createNode',
-      entity: 'node',
-      nodeId,
-      layout,
-      timestamp: startTime,
-      source: LayoutSource.External,
-      actor: 'test-actor'
-    })
-
-    // Move node
-    layoutStore.applyOperation({
-      type: 'moveNode',
-      entity: 'node',
-      nodeId,
-      position: { x: 150, y: 150 },
-      timestamp: startTime + 100,
-      source: LayoutSource.Vue,
-      actor: 'test-actor'
-    })
-
-    // Get operations by actor
-    const operations = layoutStore.getOperationsByActor('test-actor')
-    expect(operations.length).toBeGreaterThanOrEqual(2)
-    expect(operations[0].type).toBe('createNode')
-    expect(operations[1].type).toBe('moveNode')
-
-    // Get operations since timestamp
-    const recentOps = layoutStore.getOperationsSince(startTime + 50)
-    expect(recentOps.length).toBeGreaterThanOrEqual(1)
-    expect(recentOps[0].type).toBe('moveNode')
-  })
-
   it('normalizes DOM-sourced heights before storing', () => {
     const nodeId = toNodeId('dom-node')
     const layout = createTestNode(nodeId)

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

@@ -101,7 +101,6 @@ class LayoutStoreImpl implements LayoutStore {
   private ynodes: Y.Map<NodeLayoutMap> // Maps nodeId -> NodeLayoutMap containing NodeLayout data
   private yreroutes: Y.Map<Y.Map<unknown>> // Maps rerouteId -> Y.Map containing reroute data
   private ygroups: Y.Map<GroupLayoutMap> // Maps groupId -> GroupLayoutMap containing GroupLayout data
-  private yoperations: Y.Array<LayoutOperation> // Operation log
 
   // Vue reactivity layer
   private version = 0
@@ -183,7 +182,6 @@ class LayoutStoreImpl implements LayoutStore {
     this.ynodes = this.ydoc.getMap('nodes')
     this.yreroutes = this.ydoc.getMap('reroutes')
     this.ygroups = this.ydoc.getMap('groups')
-    this.yoperations = this.ydoc.getArray('operations')
 
     // Initialize spatial index managers
     this.spatialIndex = new SpatialIndexManager<NodeId>()
@@ -833,10 +831,6 @@ class LayoutStoreImpl implements LayoutStore {
 
     // Use Yjs transaction for atomic updates
     this.ydoc.transact(() => {
-      // Add operation to log
-      this.yoperations.push([operation])
-
-      // Apply the operation
       this.applyOperationInTransaction(operation, change)
     }, this.currentActor)
 
@@ -1363,27 +1357,6 @@ class LayoutStoreImpl implements LayoutStore {
     }
   }
 
-  // CRDT-specific methods
-  getOperationsSince(timestamp: number): LayoutOperation[] {
-    const operations: LayoutOperation[] = []
-    this.yoperations.forEach((op: LayoutOperation) => {
-      if (op && op.timestamp > timestamp) {
-        operations.push(op)
-      }
-    })
-    return operations
-  }
-
-  getOperationsByActor(actor: string): LayoutOperation[] {
-    const operations: LayoutOperation[] = []
-    this.yoperations.forEach((op: LayoutOperation) => {
-      if (op && op.actor === actor) {
-        operations.push(op)
-      }
-    })
-    return operations
-  }
-
   /**
    * Get the Yjs document for network sync (future feature)
    */