Feat: Vue Node Slot Improvements (#6359)

## Summary

Several fixes and improvements to the slot behavior on Vue nodes.

## Changes

- **What**: Restore the pseudo-slots, if there are slots being hidden by
collapse
- **What**: Connections while collapsed
- **What**: Display the links in a more reasonable location
- **What**: Fixes styling of linked widgets
- **What**: [~Fix reconnecting logic to prioritize newly disconnected
and now empty
slots~](https://github.com/Comfy-Org/ComfyUI_frontend/pull/6370)

## Review Focus

<!-- Critical design decisions or edge cases that need attention -->

<!-- If this PR fixes an issue, uncomment and update the line below -->
<!-- Fixes #ISSUE_NUMBER -->

## Screenshots (if applicable)


https://github.com/user-attachments/assets/913cfb8f-acdd-4f3d-b619-c280cc11cce5


<!-- Add screenshots or video recording to help explain your changes -->

┆Issue is synchronized with this [Notion
page](https://www.notion.so/PR-6359-WIP-Collapsed-nodes-multislots-29b6d73d3650817289d5f0a8efdade84)
by [Unito](https://www.unito.io)

---------

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

src/lib/litegraph/src/LGraphCanvas.ts

@@ -2672,7 +2672,7 @@ export class LGraphCanvas
       ): boolean {
         const outputLinks = [
           ...(output.links ?? []),
-          ...[...(output._floatingLinks ?? new Set())]
+          ...(output._floatingLinks ?? new Set())
         ]
         return outputLinks.some(
           (linkId) =>