## Summary
Enable node snap to grid in vue nodes mirroring the same behavior as
litegraph.
- Show node snap preview (semi transparent white box target behind node)
- Resize snap to grid
- Shift + drag / Auto snap
- Multi select + group snap
## Changes
- **What**: useNodeSnap.ts useShifyKeySync.ts setups the core hooks into
both the vue node positioning/resizing system and the event forwarding
technique for communicating to litegraph.
## Review Focus
Both new composables and specifically the useNodeLayout modifications to
batch the mutations when snapping.
A key tradeoff/note is why we are using the useShifyKeySync.ts which
dispatches a new shift event to the canvas layer. This approach is the
cleaner / more declaritive method mimicking how other vue node ->
litegraph realtime events are passed.
<!-- If this PR fixes an issue, uncomment and update the line below -->
<!-- Fixes #ISSUE_NUMBER -->
## Screenshots (if applicable)
<!-- Add screenshots or video recording to help explain your changes -->
┆Issue is synchronized with this [Notion
page](https://www.notion.so/PR-5973-Fix-vue-nodes-snap-to-grid-2866d73d365081c1a058d223c8c52576)
by [Unito](https://www.unito.io)
