fix: prevent node height shrinking on vueNodes/litegraph mode switch (#8697)

## Summary
Three interacting bugs caused cumulative height loss (~66px per cycle):

1. useVueNodeLifecycle incorrectly subtracted NODE_TITLE_HEIGHT from
LGraphNode.size[1] during layout init, but size[1] is already
content-only (title excluded per LGraphNode.measure()).

2. ensureCorrectLayoutScale added/subtracted NODE_TITLE_HEIGHT in scale
formulas, breaking the round-trip.
Simplified to pure ratio scaling (size * scaleFactor). 
Also set LayoutSource.Canvas before batchUpdateNodeBounds to prevent
stale DOM source from triggering incorrect height normalization.

3. initSizeStyles set --node-height (min-height of the full DOM element
including title) to the content-only layout height.
Added NODE_TITLE_HEIGHT so ResizeObserver captures the correct total
height and normalization recovers the exact content height.

## Screenshots (if applicable)
before

https://github.com/user-attachments/assets/ae41124b-f9e3-4061-8127-eeacddc67a55

after

https://github.com/user-attachments/assets/5ff288a6-73a3-481a-a750-150d9bdbc8fe

┆Issue is synchronized with this [Notion
page](https://www.notion.so/PR-8697-fix-prevent-node-height-shrinking-on-vueNodes-litegraph-mode-switch-2ff6d73d365081c7a2acdc7ec57e2e19)
by [Unito](https://www.unito.io)

---------

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

src/composables/graph/useVueNodeLifecycle.ts

@@ -9,7 +9,6 @@ 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'
 
@@ -33,10 +32,7 @@ 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], removeNodeTitleHeight(node.size[1])] as [
-        number,
-        number
-      ]
+      size: [node.size[0], node.size[1]] as [number, number]
     }))
     layoutStore.initializeFromLiteGraph(nodes)