fix: Vue Node <-> Litegraph node height offset normalization (#6966)

## Summary

Changes the layout store to treat node sizes as body-only measurements
while LiteGraph continues to reason about full heights. DOM-driven
updates are tagged with `LayoutSource.DOM`, which lets the store strip
the title height exactly once before persisting. That classification (a
new mutation source - `LayoutSource.DOM`) is accurate because those
mutations are triggered by the browser’s layout engine via
ResizeObserver, rather than by direct calls into the layout APIs (e.g.,
`moveNodeTo`, `useNodeDrag`). So all sources are:

- `LayoutSource.DOM`: browser layout/ResizeObserver measurements that
include the title bar
- `LayoutSource.Vue`: direct Vue-driven mutations routed through the
layout store
- `LayoutSource.Canvas`: legacy LiteGraph/canvas updates that will be
phased out over time
- `LayoutSource.External`: for multiplayer or syncing with a when going
online after making changes offline (in teams/workspace)

When layout state flows back into LiteGraph we add the title height just
in time for `liteNode.setSize`, so LiteGraph’s rendering stays
unchanged. This makes Vue node resizing and workflow persistence
deterministic - multiline widgets hold their dimensions across reloads
because every path that crosses the layout/LiteGraph boundary performs
the same normalization.

┆Issue is synchronized with this [Notion
page](https://www.notion.so/PR-6966-normalize-height-at-sites-2b76d73d365081b6bcb4f4ce6a27663a)
by [Unito](https://www.unito.io)

---------

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

src/composables/graph/useVueNodeLifecycle.ts

@@ -10,6 +10,7 @@ import { useCanvasStore } from '@/renderer/core/canvas/canvasStore'
 import { useLayoutMutations } from '@/renderer/core/layout/operations/layoutMutations'
 import { layoutStore } from '@/renderer/core/layout/store/layoutStore'
 import { useLayoutSync } from '@/renderer/core/layout/sync/useLayoutSync'
+import { removeNodeTitleHeight } from '@/renderer/core/layout/utils/nodeSizeUtil'
 import { ensureCorrectLayoutScale } from '@/renderer/extensions/vueNodes/layout/ensureCorrectLayoutScale'
 import { app as comfyApp } from '@/scripts/app'
 import { useToastStore } from '@/platform/updates/common/toastStore'
@@ -38,7 +39,10 @@ function useVueNodeLifecycleIndividual() {
     const nodes = activeGraph._nodes.map((node: LGraphNode) => ({
       id: node.id.toString(),
       pos: [node.pos[0], node.pos[1]] as [number, number],
-      size: [node.size[0], node.size[1]] as [number, number]
+      size: [node.size[0], removeNodeTitleHeight(node.size[1])] as [
+        number,
+        number
+      ]
     }))
     layoutStore.initializeFromLiteGraph(nodes)